. 
AN  INTRODUCTION  TO 

THE  HISTORY  OF  SCIENCE 


BY 


WALTER  LIBBY,  M.A.,  Ph.D. 

PROFESSOR   OF   THE   HISTORY   OF   SCIENCE 

IN   THE   CARNEGIE  INSTITUTE 

OF  TECHNOLOGY 


BOSTON   NEW   YORK    CHICAGO 

HOUGHTON  MIFFLIN  COMPANY 
fttoetfi&e  pretf  Cambribge 


V 


COPYRIGHT,   1917,   BY  WALTER  LIBBY 
ALL  RIGHTS  RESERVED 


CAMBRIDGE  .  MASSACHUSETTS 
U   .    S   .    A 


TO  MY  STUDENTS  OP  THE  LAST  TWELVE 
YEARS  IN  THE  CHICAGO  AND  PITTSBURGH 
DISTRICTS  THIS  BOOK  IS  INSCRIBED  IN 
FURTHERANCE  OF  THE  ENDEAVOR  TO 
INCULCATE  A  DEMOCRATIC  CULTURE, 
EVER  MINDFUL  OF  THE  DAILY  TASK, 
NOT  ALTOGETHER  IGNORANT  OF  THE 
ACHIEVEMENTS  OF  THE  PAST 


358887 


PREFACE 

THE  history  of  science  has  something  to  offer  to 
the  humblest  intelligence.  It  is  a  means  of  impart- 
ing a  knowledge  of  scientific  facts  and  principles  to 
unschooled  minds.  At  the  same  time  it  affords  a 
simple  method  of  school  instruction.  Those  who 
understand  a  business  or  an  institution  best,  as  a 
contemporary  writer  on  finance  remarks,  are  those 
who  have  made  it  or  grown  up  with  it,  and  the  next 
best  thing  is  to  know  how  it  has  grown  up,  and  then 
watch  or  take  part  in  its  actual  working.  Generally 
speaking,  we  know  best  what  we  know  in  its  origins. 

The  history  of  science  is  an  aid  in  scientific  research. 
It  places  the  student  in  the  current  of  scientific 
thought,  and  gives  him  a  clue  to  the  purpose  and 
necessity  of  the  theories  he  is  required  to  master.  It 
presents  science  as  the  constant  pursuit  of  truth 
rather  than  the  formulation  of  truth  long  since  re- 
vealed ;  it  shows  science  as  progressive  rather  than 
fixed,  dynamic  rather  than  static,  a  growth  to  which 
each  may  contribute.  It  does  not  paralyze  the  self- 
activity  of  youth  by  the  record  of  an  infallible  past. 

It  is  only  by  teaching  the  sciences  in  their  histori- 
cal development  that  the  schools  can  be  true  to  the 
two  principles  of  modern  education,  that  the  sciences 
should  occupy  the  foremost  place  in  the  curriculum 
and  that  the  individual  mind  in  its  evolution  should 
rehearse  the  history  of  civilization. 

The  history  of  science  should  be  given  a  larger 
place  than  at  present  in  general  history ;  for,  as 


vi  PREFACE 

Bacon  said,  the  history  of  the  world  without  a  his- 
tory of  learning  is  like  a  statue  of  Polyphemus  with 
the  eye  out.  The  history  of  science  studies  the  past 
for  the  sake  of  the  future.  It  is  a  story  of  continu- 
ous progress.  It  is  rich  in  biographical  material.  It 
shows  the  sciences  in  their  interrelations,  and  saves 
the  student  from  narrowness  and  premature  special- 
ization. It  affords  a  unique  approach  to  the  study 
of  philosophy.  It  gives  new  motive  to  the  study  of 
foreign  languages.  It  gives  an  interest  in  the  ap- 
plications of  knowledge,  offers  a  clue  to  the  complex 
civilization  of  the  present,  and  renders  the  mind  hos- 
pitable to  new  discoveries  and  inventions. 

The  history  of  science  is  hostile  to  the  spirit  of 
caste.  It  shows  the  sciences  rising  from  daily  needs 
and  occupations,  formulated  by  philosophy,  enrich- 
ing philosophy,  giving  rise  to  new  industries,  which 
react  in  turn  upon  the  sciences.  The  history  of  sci- 
ence reveals  men  of  all  grades  of  intelligence  and 
of  all  social  ranks  cooperating  in  the  cause  of  human 
progress.  It  is  a  basis  of  intellectual  and  social  homo- 
geneity. 

Science  is  international,  English,  Germans,  French, 
Italians,  Russians — all  nations  —  contributing  to 
advance  the  general  interests.  Accordingly,  a  survey 
of  the  sciences  tends  to  increase  mutual  respect,  and 
to  heighten  the  humanitarian  sentiment.  The  history 
of  science  can  be  taught  to  people  of  all  creeds  and 
colors,  and  cannot  fail  to  enhance  in  the  breast  of 
every  young  man,  or  woman,  faith  in  human  progress 
and  good-will  to  all  mankind. 

This  book  is  intended  as  a  simple  introduction, 
taking  advantage  of  the  interests  of  youth  of  from 


.  PREFACE  vii 

seventeen  to  twenty-two  years  of  age  (and  their  in- 
tellectual compeers)  in  order  to  direct  their  atten- 
tion to  the  story  of  the  development  of  the  sciences. 
It  makes  no  claim  to  be  in  any  sense  complete  or 
comprehensive.  It  is,  therefore,  a  psychological  in- 
troduction, having  the  mental  capacity  of  a  certain 
class  of  readers  always  in  view,  rather  than  a  logical 
introduction,  which  would  presuppose  in  all  readers 
both  full  maturity  of  intellect  and  considerable  ini- 
tial interest  in  the  history  of  science. 

I  cannot  conclude  this  preface  without  thanking 
those  who  have  assisted  me  in  the  preparation  of 
this  book  —  Sir  William  Osier,  who  read  the  first 
draft  of  the  manuscript,  and  aided  me  with  his  coun- 
sel ;  Dr.  Charles  Singer,  who  read  all  the  chapters  in 
manuscript,  and  to  whom  I  am  indebted  for  advice 
in  reference  to  the  illustrations  and  for  many  other 
valuable  suggestions ;  the  officers  of  the  Bodleian  Li- 
brary, whose  courtesy  was  unfailing  during  the  year 
I  worked  there ;  Professor  Henry  Crew,  who  helped 
in  the  revision  of  two  of  the  chapters  by  his  judicious 
criticism ;  Professor  J.  E.  Rush,  whose  knowledge 
of  bacteriology  improved  the  chapter  on  Pasteur ; 
Professor  L.  O.  Grondahl,  who  read  one  of  the  chap- 
ters relating  to  the  history  of  physics  and  suggested 
important  emendations ;  and  Dr.  John  A.  Brashear, 
who  contributed  valuable  information  in  reference  to 
the  activities  of  Samuel  Pierpont  Langley.  I  wish  to 
express  my  gratitude  also  to  Miss  Florence  Bonnet 
for  aid  in  the  correction  of  the  manuscript. 

W. 

February  2,  1917. 


CONTENTS 

I.  SCIENCE   AND   PRACTICAL   NEEDS  —  EGYPT 

AND  BABYLONIA 1 

n.  THE  INFLUENCE  OF  ABSTRACT  THOUGHT  — 

GREECE:  ARISTOTLE       15 

HI.  SCIENTIFIC  THEORY  SUBORDINATED  TO  ,W 

PLICATION  —  ROME:  VITRUVIUS  ....    30 

IV.  THE  CONTINUITY  OF  SCIENCE  —  THE  MEDI- 
EVAL CHURCH  AND  THE  ARABS  ....    43 

V.  THE   CLASSIFICATION  OF  THE   SCIENCES  — 

FRANCIS  BACON 57 

VI.  SCIENTIFIC    METHOD  —  GILBERT,    GALILEO, 

HARVEY,  DESCARTES 72 

VII.  SCIENCE  AS  MEASUREMENT  —  TYCHO  BRAHE, 

KEPLER,  BOYLE 86 

VIII.  COOPERATION    IN    SCIENCE  —  THE    ROYAL 

SOCIETY 99 

IX.  SCIENCE  AND  THE  STRUGGLE  FOR  LIBERTY  — 

BENJAMIN  FRANKLIN 114 

X.  THE  INTERACTION  OF  THE  SCIENCES  — 
WERNER,  HUTTON,  BLACK,  HALL,  WILLIAM 
SMITH 129 

XI.  SCIENCE  AND  RELIGION  —  KANT,  LAMBERT, 

LAPLACE,  SIR  WILLIAM  HERSCHEL  .     .     .  142 

XII.  THE  REIGN  OF  LAW  —  DALTON,  JOULE  .    .  155 


x  CONTENTS 

XIII.  THE  SCIENTIST  —  SIR  HUMPHRY  DAVY  .    .  170 

XIV.  SCIENTIFIC   PREDICTION  —  THE  DISCOVERY 

OF  NEPTUNE 184 

XV.  SCIENCE  AND  TRAVEL  —  THE    VOYAGE    OF 

THE  BEAGLE 197 

XVI.  SCIENCE  AND  WAR  — PASTEUR,  LISTER  .    .  213 

XVII.  SCIENCE  AND  INVENTION  —  LANGLEY'S  AERO- 
PLANE   231 

XVEU.  SCIENTIFIC  HYPOTHESIS  —  RADIOACTIVE  SUB- 
STANCES     245 

XIX.  THE  SCIENTIFIC  IMAGINATION 258 

XX.  SCIENCE  AND  DEMOCRATIC  CULTURE  .    .    .  270 
INDEX  .  283 


ILLUSTRATIONS 

EARLIEST  PICTURE  KNOWN  OF  A  SURGICAL  OPERA- 
TION.   EGYPT,  2500  B.C 6 

ST.  THOMAS  AQUINAS  OVERCOMING  AVERROES      .    %  54 

DR.  GILBERT  SHOWING  HIS  ELECTRICAL  EXPERIMENTS 
TO  QUEEN  ELIZABETH  AND  HER  COURT  ....    72 

THE  TICHONIC  QUADRANT 88 

WADHAM  COLLEGE,  OXFORD 104 

SIR  ISAAC  NEWTON  . 112 

JOHN  DALTON  COLLECTING  MARSH  GAS      ....  162 

THE  FIRST  SUCCESSFUL  HEAVIER-THAN-AIR  FLYING 
MACHINE  .  236 


AN  INTRODUCTION  TO  THE 
HISTORY  OF  SCIENCE 

CHAPTER  I 

SCIENCE   AND    PRACTICAL  NEEDS  —  EGYPT   AND 
BABYLONIA 

IF  you  consult  encyclopedias  and  special  works  in 
reference  to  the  early  history  of  any  one  of  the  sci- 
ences, —  astronomy,  geology,  geometry,  physiology, 
logic,  or  political  science,  for  example, — you  will  find 
strongly  emphasized  the  part  played  by  the  Greeks 
in  the  development  of  organized  knowledge.  Great, 
indeed,  as  we  shall  see  in  the  next  chapter,  are  the 
contributions  to  the  growth  of  science  of  this  highly 
rational  and  speculative  people.  It  must  be  conceded, 
also,  that  the  influence  on  Western  science  of  civili- 
zations earlier  than  theirs  has  come  to  us,  to  a  con- 
siderable extent  at  least,  through  the  channels  of 
Greek  literature. 

Nevertheless,  if  you  seek  the  very  origins  of  the 
sciences,  you  will  inevitably  be  drawn  to  the  banks 
of  the  Nile,  and  to  the  valleys  of  the  Tigris  and  the 
Euphrates.  Here,  in  Egypt,  in  Assyria  and  Babylonia, 
dwelt  from  very  remote  times  nations  whose  genius 
was  practical  and  religious  rather  than  intellectual 
and  theoretical,  and  whose  mental  life,  therefore,  was 
more  akin  to  our  own  than  was  the  highly  evolved 
culture  of  the  Greeks.  Though  more  remote  in  time, 


!«:       THE  :msTofty  OF  SCIENCE 

the  wisdom  and  practical  knowledge  of  Thebes  and 
Memphis,  Nineveh  and  Babylon,  are  more  readily 
comprehended  by  our  minds  than  the  difficult  spec- 
ulations of  Athenian  philosophy. 

Much  that  we  have  inherited  from  the  earliest 
civilizations  is  so  familiar,  so  homely,  that  we  simply 
accept  it,  much  as  we  may  light,  or  air,  or  water, 
without  analysis,  without  inquiry  as  to  its  origin, 
and  without  full  recognition  of  how  indispensable  it 
is.  Why  are  there  seven  days  in  the  week,  and  not 
eight  ?  Why  are  there  sixty  minutes  in  the  hour,  and 
why  are  there  not  sixty  hours  in  the  day?  These 
artificial  divisions  of  time  are  accepted  so  unquestion- 
ingly  that  to  ask  a  reason  for  them  may,  to  an  indolent 
mind,  seem  almost  absurd.  This  acceptance  of  a  week 
of  seven  days  and  of  an  hour  of  sixty  minutes  (almost 
as  if  they  were  natural  divisions  of  time  like  day  and 
night)  is  owing  to  a  tradition  that  is  Babylonian  in 
its  origin.  From  the  Old  Testament  (which  is  one 
of  the  greatest  factors  in  preserving  the  continuity 
of  human  culture,  and  the  only  ancient  book  which 
speaks  with  authority  concerning  Babylonian  history) 
we  learn  that  Abraham,  the  progenitor  of  the  He- 
brews, migrated  to  the  west  from  southern  Babylonia 
about  twenty-three  hundred  years  before  Christ. 
Even  in  that  remote  age,  however,  the  Babylonians 
had  established  those  divisions  of  time  which  are 
familiar  to  us.  The  seven  days  of  the  week  were 
closely  associated  in  men's  thinking  with  the  heav- 
enly bodies.  In  our  modern  languages  they  are  named 
after  the  sun,  the  moon,  Mars,  Mercury,  Jupiter, 
Venus,  and  Saturn,  which  from  the  remotest  times 
were  personified  and  worshiped.  Thus  we  see  that 


SCIENCE   AND   PRACTICAL   NEEDS     3 

the  usage  of  making  seven  days  a  unit  of  time  de- 
pends on  the  religious  belief  and  astronomical  science 
of  a  very  remote  civilization.  The  usage  is  so  com- 
pletely established  that  by  the  majority  it  is  simply 
taken  for  granted. 

Another  piece  of  commonplace  knowledge  —  the 
cardinal  points  of  the  compass  —  may  be  accepted, 
likewise,  without  inquiry  or  without  recognition  of  its 
importance.  Unless  thrown  on  your  own  resources  in 
an  unsettled  country  or  on  unknown  waters,  you  may 
long  fail  to  realize  how  indispensable  to  the  practical 
conduct  of  life  is  the  knowledge  of  east  and  west  and 
north  and  south.  In  this  matter,  again,  the  records 
of  ancient  civilizations  show  the  pains  that  were  taken 
to  fix  these  essentials  of  science.  Modern  excava- 
tions have  demonstrated  that  the  sides  or  the  corners 
of  the  temples  and  palaces  of  Assyria  and  Babylo- 
nia were  directed  to  the  four  cardinal  points  of  the 
compass.  In  Egypt  the  pyramids,  erected  before 
3000  B.C.,  were  laid  out  with  such  strict  regard  to 
direction  that  the  conjecture  has  been  put  forward 
that  their  main  purpose  was  to  establish,  in  a  land 
of  shifting  sands,  east  and  west  and  north  and  south. 
That  conjecture  seems  extravagant;  but  the  fact  that 
the  Phoenicians  studied  astronomy  merely  because  of 
its  practical  value  in  navigation,  the  early  invention 
of  the  compass  in  China,  the  influence  on  discovery 
of  the  later  improvements  of  the  compass,  make  us 
realize  the  importance  of  the  alleged  purpose  of  the 
pyramids.  Without  fixed  points,  without  something 
to  go  by,  men,  before  they  had  acquired  the  elements 
of  astronomy,  were  altogether  at  sea.  As  they  ad- 
vanced in  knowledge  they  looked  to  the  stars  for 


4  THE   HISTORY  OF   SCIENCE 

guidance,  especially  to  the  pole  star  and  the  imperish- 
able star-group  of  the  northern  heavens.  The  Egyp- 
tians even  developed  an  apparatus  for  telling  the 
time  by  reference  to  the  stars  —  a  star-clock  similar 
in  its  purpose  to  the  sundial.  By  the  Egyptians, 
also,  was  carefully  observed  the  season  of  the  year 
at  which  certain  stars  and  constellations  were  visible 
at  dawn.  This  was  of  special  importance  in  the  case 
of  Sirius,  for  its  heliacal  rising,  that  is,  the  period 
when  it  rose  in  conjunction  with  the  sun,  marked 
the  coming  of  the  Nile  flood  (so  important  in  the 
lives  of  the  inhabitants)  and  the  beginning  of  a 
new  year.  Not  unnaturally  Sirius  was  an  object  of 
worship.  One  temple  is  said  to  have  been  so  con- 
structed as  to  face  that  part  of  the  eastern  horizon 
at  which  this  star  arose  at  the  critical  season  of  in- 
undation. Of  another  temple  we  are  told  that  only 
at  sunset  at  the  time  of  the  summer  solstice  did  the 
sun  throw  its  rays  throughout  the  edifice.  The  fact 
that  astronomy  in  Egypt  as  in  Babylonia,  where 
the  temples  were  observatories,  was  closely  associated 
with  religion  confirms  the  view  that  this  science  was 
first  cultivated  because  of  its  bearing  on  the  practical 
needs  of  the  people.  The  priests  were  the  preservers 
of  such. wisdom  as  had  been  accumulated  in  the 
course  of  man's  immemorial  struggle  with  the  forces 
of  nature. 

It  is  well  known  that  geometry  had  its  origin  in 
the  valley  of  the  Nile,  that  it  arose  to  meet  a  practi- 
cal need,  and  that  it  was  in  the  first  place,  as  its  name 
implies,  a  measurement  of  the  earth  —  a  crude  sur- 
veying, employed  in  the  restoration  of  boundaries 
obliterated  by  the  annual  inundations  of  the  river. 


SCIENCE   AND   PRACTICAL   NEEDS     5 

Egyptian  geometry  cared  little  for  theory.  It  ad- 
dressed itself  to  actual  problems,  such  as  determin- 
ing the  area  of  a  square  or  triangular  field  from  the 
length  of  the  sides.  To  find  the  area  of  a  circular 
field,  or  floor,  or  vessel,  from  the  length  of  the  diame- 
ter was  rather  beyond  the  science  of  2000  B.C.  This 
was,  however,  a  practical  problem  which  had  to  be 
solved,  even  if  the  solution  were  not  perfect.  The  prac- 
tice was  to  square  the  diameter  reduced  by  one  ninth. 

In  all  the  Egyptian  mathematics  of  which  we  have 
record  there  is  to  be  observed  a  similar  practical  bent. 
In  the  construction  of  a  temple  or  a  pyramid  not 
merely  was  it  necessary  to  have  regard  to  the  points 
of  the  compass,  but  care  must  be  taken  to  have  the 
sides  at  right  angles.  This  required  the  intervention 
of  specialists,  expert  "  rope-fasteners,"  who  laid  off  a 
triangle  by  means  of  a  rope  divided  into  three  parts, 
of  three,  four,  and  five  units.  The  Babylonians  fol- 
lowed much  the  same  practice  in  fixing  a  right  angle. 
In  addition  they  learned  how  to  bisect  and  trisect  the 
angle.  Hence  we  see  in  their  designs  and  ornaments 
the  division  of  the  circle  into  twelve  parts,  a  division 
which  does  not  appear  in  Egyptian  ornamentation  till 
after  the  incursion  of  Babylonian  influence. 

There  is  no  need,  however,  to  multiply  examples ; 
the  tendency  of  all  Egyptian  mathematics  was,  as 
already  stated,  concerned  with  the  practical  solution 
of  concrete  problems  —  mensuration,  the  cubical  con- 
tents of  barns  and  granaries,  the  distribution  of  bread, 
the  amounts  of  food  required  by  men  and  animals 
in  given  numbers  and  for  given  periods  of  time,  the 
proportions  and  the  angle  of  elevation  (about  52°) 
of  a  pyramid,  etc.  Moreover,  they  worked  simple 


6  THE  HISTORY  OF   SCIENCE 

equations  involving  one  unknown,  and  had  a  hiero- 
glyph for  a  million  (the  drawing  of  a  man  overcome 
with  wonder),  and  another  for  ten  million. 

The  Rhind  mathematical  papyrus  in  the  British 
Museum  is  the  main  source  of  our  present  knowledge 
of  early  Egyptian  arithmetic,  geometry,  and  of  what 
might  be  called  their  trigonometry  and  algebra.  It 
describes  itself  as  "Instructions  for  arriving  at  the 
knowledge  of  all  things,  and  of  things  obscure,  and 
of  all  mysteries."  It  was  copied  by  a  priest  about 
1600  B.C.  — the  classical  period  of  Egyptian  culture 
—  from  a  document  seven  hundred  years  older. 

Medicine,  which  is  almost  certain  to  develop  in  the 
early  history  of  a  people  in  response  to  their  urgent 
needs,  has  been  justly  called  the  foster-mother  of 
many  sciences.  In  the  records  of  Egyptian  medical 
practice  can  be  traced  the  origin  of  chemistry,  anat- 
omy, physiology,  and  botany.  Our  most  definite  in- 
formation concerning  Egyptian  medicine  belongs  to 
the  same  general  period  as  the  mathematical  docu- 
ment to  which  we  have  just  referred.  It  is  true  some- 
thing is  known  of  remoter  times.  The  first  physician 
of  whom  history  has  preserved  the  name,  I-em-hetep 
(He-who-cometh-in-peace),  lived  about  4500  B.C. 
Recent  researches  have  also  brought  to  light,  near 
Memphis,  pictures,  not  later  than  2500  B.C.,  of  surgi- 
cal operations.  They  were  found  sculptured  on  the 
doorposts  at  the  entrance  to  the  tomb  of  a  high  official 
of  one  of  the  Pharaohs.  The  patients,  as  shown  in 
the  accompanying  illustration,  are  suffering  pain,  and, 
according  to  the  inscription,  one  cries  out,  "Do  this 
[and]  let  me  go,"  and  the  other,  "  Don't  hurt  me 
so ! "  Our  most  satisfactory  data  in  reference  to  Egyp- 


SCIENCE   AND   PRACTICAL  NEEDS     7 

tian  medicine  are  derived,  however,  from  the  Ebers 
papyrus.  This  document  displays  some  little  knowl- 
edge of  the  pulse  in  different  parts  of  the  body,  of  a 
relation  between  the  heart  and  the  other  organs,  and 
of  the  passage  of  the  breath  to  the  lungs  (and  heart). 
It  contains  a  list  of  diseases.  In  the  main  it  is  a  col- 
lection of  prescriptions  for  the  eyes,  ears,  stomach, 
to  reduce  tumors,  effect  purgation,  etc.  There  is  no 
evidence  of  a  tendency  to  homeopathy,  but  mental 
healing  seems  to  have  been  called  into  play  by  the 
use  of  numerous  spells  and  incantations.  Each  pre- 
scription, as  in  medical  practice  to-day,  contains  as 
a  rule  several  ingredients.  Among  the  seven  hundred 
recognized  remedies  are  to  be  noted  poppy,  castor- 
oil,  gentian,  colchicum,  squills,  and  many  other  fa- 
miliar medicinal  plants,  as  well  as  bicarbonate  of  soda, 
antimony,  and  salts  of  lead  and  copper.  The  fat  of 
the  lion,  hippopotamus,  crocodile,  goose,  serpent,  and 
wild  goat,  in  equal  parts,  served  as  a  prescription  for 
baldness.  In  the  interests  of  his  art  the  medical  prac- 
titioner ransacked  the  resources  of  organic  and  in- 
organic nature.  The  Ebers  papyrus  shows  that  the 
Egyptians  knew  of  the  development  of  the  beetle  from 
the  egg,  of  the  blow-fly  from  the  larva,  and  of  the 
frog  from  the  tadpole.  Moreover,  for  precision  in  the 
use  of  medicaments  weights  of  very  small  denomi- 
nations were  employed. 

The  Egyptian  embalmers  relied  on  the  preserva- 
tive properties  of  common  salt,  wine,  aromatics, 
myrrh,  cassia,  etc.  By  the  use  of  linen  smeared  with 
gum  they  excluded  all  putrefactive  agencies.  They 
understood  the  virtue  of  extreme  dryness  in  the 
exercise  of  their  antiseptic  art.  Some  knowledge  of 


8  THE  HISTORY  OF  SCIENCE 

anatomy  was  involved  in  the  removal  of  the  viscera, 
and  much  more  in  a  particular  method  they  followed 
in  removing  the  brain. 

In  their  various  industries  the  Egyptians  made 
use  of  gold,  silver,  bronze  (which  on  analysis  is 
found  to  consist  of  copper,  tin,  and  a  trace  of  lead, 
etc.),  metallic  iron  and  copper  and  their  oxides, 
manganese,  cobalt,  alum,  cinnabar,  indigo,  madder, 
brass,  white  lead,  lampblack.  There  is  clear  evidence 
that  they  smelted  iron  ore  as  early  as  3400  B.C. 
maintaining  a  blast  by  means  of  leather  tread-bel- 
lows. They  also  contrived  to  temper  the  metal,  and 
to  make  helmets,  swords,  lance-points,  ploughs,  tools, 
and  other  implements  of  iron.  Besides  metallurgy 
they  practiced  the  arts  of  weaving,  dyeing,  distilla- 
tion. They  produced  soap  (from  soda  and  oil), 
transparent  and  colored  glass,  enamel,  and  ceramics. 
They  were  skilled  in  the  preparation  of  leather. 
They  showed  aptitude  for  painting,  and  for  the  other 
fine  arts.  They  were  expert  builders,  and  possessed  the 
engineering  skill  to  erect  obelisks  weighing  hundreds 
of  tons.  They  cultivated  numerous  vegetables,  grains, 
fruits,  and  flowers.  They  had  many  domestic  ani- 
mals. In  seeking  the  satisfaction  of  their  practical 
needs  they  laid  the  foundation  of  geometry,  botany, 
chemistry  (named,  as  some  think,  from  the  Egyptian 
Khem,  the  god  of  medicinal  herbs),  and  other  sci- 
ences. But  their  practical  achievements  far  tran- 
scended their  theoretical  formulations.  To  all  time 
they  will  be  known  as  an  artistic,  noble,  and  reli- 
gious people,  who  cherished  their  dead  and  would 
not  allow  that  the  good  and  beautiful  and  great 
should  altogether  pass  away. 


SCIENCE   AND   PRACTICAL   NEEDS     9 

Excavations  in  Assyria  and  Babylonia,  especially 
since  1843,  have  brought  to  our  knowledge  an  an- 
cient culture  stretching  back  four  or  five  thousand 
years  before  the  beginning  of  the  Christian  era.  The 
records  of  Assyria  and  Babylonia,  like  those  of  Egypt, 
are  fragmentary  and  still  in  need  of  interpretation. 
Here  again,  however,  it  is  the  fundamental,  the  in- 
dispensable, the  practical  forms  of  knowledge  that 
stand  revealed  rather  than  the  theoretical,  specula- 
tive, and  purely  intellectual. 

By  the  Babylonian  priests  the  heavens  were  made 
the  object  of  expert  observation  as  early  as  3800  B.C. 
The  length  of  the  year,  the  length  of  the  month,  the 
coming  of  the  seasons,  the  course  of  the  sun  in  the 
heavens,  the  movements  of  the  planets,  the  recur- 
rence of  eclipses,  comets,  and  meteors,  were  studied 
with  particular  care.  One  motive  was  the  need  of  a 
measurement  of  time,  the  same  motive  as  underlies 
the  common  interest  in  the  calendar  and  almanac. 
It  was  found  that  the  year  contained  more  than  365 
days,  the  month  (synodic)  more  than  29  days,  12 
hours,  and  44  minutes.  The  sun's  apparent  diameter 
was  contained  720  times  in  the  ecliptic,  that  is,  in 
the  apparent  path  of  the  sun  through  the  heavens. 
Like  the  Egyptians,  the  Babylonians  took  special 
note  of  the  stars  and  star-groups  that  were  to  be 
seen  at  dawn  at  different  times  of  the  year.  These 
constellations,  lying  in  the  imaginary  belt  encircling 
the  heavens  on  either  side  of  the  ecliptic,  bore  names 
corresponding  to  those  we  have  adopted  for  the  signs 
of  the  zodiac,  —  Balance,  Ram,  Bull,  Twins,  Scor- 
pion, Archer,  etc.  The  Babylonian  astronomers  also 
observed  that  the  successive  vernal  (or  autumnal) 


10          THE  HISTORY  OF  SCIENCE 

equinoxes  follow  each  other  at  intervals  of  a  few  sec- 
onds less  than  a  year. 

A  second  motive  that  influenced  the  Babylonian 
priests  in  studying  the  movements  of  the  heavenly 
bodies  was  the  hope  of  foretelling  events.  The  plan- 
ets, seen  to  shift  their  positions  with  reference  to  the 
other  heavenly  bodies,  were  called  messengers,  or 
angels.  The  appearance  of  Mars,  perhaps  on  account 
of  its  reddish  color,  was  associated  in  their  imagina- 
tions with  war.  Comets,  meteors,  and  eclipses  were 
considered  as  omens  portending  pestilence,  national 
disaster,  or  the  fate  of  kings.  The  fortunes  of  in- 
dividuals could  be  predicted  from  a  knowledge  of 
the  aspect  of  the  heavens  at  the  hour  of  their  birth. 
This  interest  in  astrology,  or  divination  by  means  of 
the  stars,  no  doubt  stimulated  the  priests  to  make 
careful  observations  and  to  preserve  religiously  the 
record  of  astronomical  phenomena.  It  was  even  es- 
tablished that  there  is  a  cycle  in  which  eclipses,  solar 
and  lunar,  repeat  themselves,  a  period  (saros)  some- 
what more  than  eighteen  years  and  eleven  months. 
Moreover,  from  the  Babylonians  we  derive  some  of 
our  most  sublime  religious  and  scientific  concep- 
tions. They  held  that  strict  law  governs  the  appar- 
ently erratic  movements  of  the  heavenly  bodies. 
Their  creation  myth  proclaims:  "Merodach  next 
arranged  the  stars  in  order,  along  with  the  sun  and 
moon,  and  gave  them  laws  which  they  were  never  to 
transgress." 

The  mathematical  knowledge  of  the  Babylonians  is 
related  on  the  one  hand  to  their  astronomy  and  on  the 
other  to  their  commercial  pursuits.  They  possessed 
highly  developed  systems  of  measuring,  weighing, 


SCIENCE  AND   PRACTICAL  NEEDS     11 

and  counting  —  processes,  which,  as  we  shall  see  in 
the  sequel,  are  essential  to  scientific  thought.  About 
2300  B.C.  they  had  multiplication  tables  running 
from  1  to  1350,  which  were  probably  used  in  con- 
nection with  astronomical  calculations.  Unlike  the 
Egyptians  they  had  no  symbol  for  a  million,  though 
the  "  ten  thousand  times  ten  thousand  "  of  the  Bible 
(Daniel  vn :  10)  may  indicate  that  the  conception 
of  even  larger  numbers  was  not  altogether  foreign 
to  them.  They  counted  in  sixties  as  well  as  in  tens. 
Their  hours  and  minutes  had  each  sixty  subdivisions. 
They  divided  the  circle  into  six  parts  and  into  six- 
times-sixty  subdivisions.  Tables  of  squares  and  cubes 
discovered  in  southern  Babylonia  were  interpreted 
correctly  only  on  a  sexagesimal  basis,  the  statement 
that  1  plus  4  is  the  square  of  8  implying  that  the  first 
unit  is  60.  As  we  have  already  seen,  considerable 
knowledge  of  geometry  is  apparent  in  Babylonian 
designs  and  constructions. 

According  to  a  Greek  historian  of  the  fifth  cen- 
tury B.C.,  there  were  no  physicians  at  Babylon,  while 
a  later  Greek  historian  (of  the  first  century  B.C.) 
speaks  of  a  Babylonian  university  which  had  at- 
tained celebrity,  and  which  is  now  believed  to  have 
been  a  school  of  medicine.  Modern  research  has 
made  known  letters  by  a  physician  addressed  to  an 
Assyrian  king  in  the  seventh  century  B.C.  referring 
to  the  king's  chief  physician,  giving  directions  for  the 
treatment  of  a  bleeding  from  the  nose  from  which  a 
friend  of  the  prince  was  suffering,  and  reporting  the 
probable  recovery  of  a  poor  fellow  whose  eyes  were 
diseased.  Other  letters  from  the  same  general  period 
mention  the  presence  of  physicians  at  court.  We  have 


12          THE   HISTORY  OF  SCIENCE 

even  recovered  the  name  (Ilu-bani)  of  a  physician 
who  lived  in  southern  Babylonia  about  2700  B.C. 
The  most  interesting  information,  however,  in  refer- 
ence to  Babylonian  medicine  dates  from  the  time  of 
Hammurabi,  a  contemporary  of  the  patriarch  Abra- 
ham. It  appears  from  the  code  drawn  up  in  the  reign 
of  that  monarch  that  the  Babylonian  surgeons  oper- 
ated in  case  of  cataract ;  that  they  were  entitled  to 
twenty  silver  shekels  (half  the  sum  for  which  Joseph 
was  sold  into  slavery,  and  equivalent  to  seven  or 
eight  dollars)  for  a  successful  operation  ;  and  that  in 
case  the  patient  lost  his  life  or  his  sight  as  the  result 
of  an  unsuccessful  operation,  the  surgeon  was  con- 
demned to  have  his  hands  amputated. 

The  Babylonian  records  of  medicine  like  those  of 
astronomy  reveal  the  prevalence  of  many  superstitious 
beliefs.  The  spirits  of  evil  bring  maladies  upon  us ; 
the  gods  heal  the  diseases  that  afflict  us.  The  Baby- 
lonian books  of  medicine  contained  strange  inter- 
minglings  of  prescription  and  incantation.  The  priests 
studied  the  livers  of  sacrificial  animals  in  order  to 
divine  the  thoughts  of  the  gods  —  a  practice  which 
stimulated  the  study  of  anatomy.  The  maintenance 
of  state  menageries  no  doubt  had  a  similar  influence 
on  the  study  of  the  natural  history  of  animals. 

The  Babylonians  were  a  nation  of  agriculturists 
and  merchants.  Sargon  of  Akkad,  who  founded  the 
first  Semitic  empire  in  Asia  (3800  B.C.),  was  brought 
up  by  an  irrigator,  and  was  himself  a  gardener.  Bel- 
shazzar,  the  son  of  the  last  Babylonian  king,  dealt 
in  wool  on  a  considerable  scale.  Excavation  in  the 
land  watered  by  the  Tigris  and  Euphrates  tells  the 
tale  of  the  money-lenders,  importers,  dyers,  fullers, 


SCIENCE   AND   PRACTICAL  NEEDS     13 

tanners,  saddlers,  smiths,  carpenters,  shoemakers, 
stonecutters,  ivory-cutters,  brickmakers,  porcelain- 
makers,  potters,  vintners,  sailors,  butchers,  engi- 
neers, architects,  painters,  sculptors,  musicians,  deal- 
ers in  rugs,  clothing  and  fabrics,  who  contributed  to 
the  culture  of  this  great  historic  people.  It  is  not 
surprising  that  science  should  find  its  matrix  in  so 
rich  a  civilization. 

The  lever  and  the  pulley,  lathes,  picks,  saws,  ham- 
mers, bronze  operating-lances,  sundials,  water-clocks, 
the  gnomon  (a  vertical  pillar  for  determining  the  sun's 
altitude)  were  in  use.  Gem-cutting  was  highly  de- 
veloped as  early  as  3800  B.C.  The  Babylonians  made 
use  of  copper  hardened  with  antimony  and  tin,  lead, 
incised  shells,  glass,  alabaster,  lapis-lazuli,  silver,  and 
gold.  Iron  was  not  employed  before  the  period  of  con- 
tact with  Egyptian  civilization.  Their  buildings  were 
furnished  with  systems  of  drains  and  flushes  that  seem 
to  us  altogether  modern.  Our  museums  are  enriched 
by  specimens  of  their  handicraft  —  realistic  statuary 
in  dolerite  of  2700  B.C. ;  rock  crystal  worked  to  the 
form  of  a  plano-convex  lens,  3800  B.C.  ;  a  beautiful 
silver  vase  of  the  period  3950  B.C. ;  and  the  head  of 
a  goat  in  copper  about  4000  B.C. 

Excavation  has  not  disclosed  nor  scholarship  in- 
terpreted the  full  record  of  this  ancient  people  in  the 
valley  of  the  Tigris  and  the  Euphrates,  not  far  from 
the  Gulf  of  Persia,  superior  in  religious  inspiration, 
not  inferior  in  practical  achievements  to  the  Egyp- 
tians. Both  these  great  nations  of  antiquity,  however, 
failed  to  carry  the  sciences  that  arose  in  connection 
with  their  arts  to  a  high  degree  of  generalization. 
That  was  reserved  for  another  people  of  ancient 
times,  namely,  the  Greeks. 


14          THE   HISTORY  OF  SCIENCE 


REFERENCES 

F.  H.  Garrison,  An  Introduction  to  the  History  of  Medicine. 
H.  V.  Hilprecht,  Excavations  in  Assyria  and  Babylonia. 
Max  Neuburger,  History  of  Medicine. 
A.  H.  Sayce,  Babylonians  and  Assyrians. 


CHAPTER  II 

THE  INFLUENCE  OF  ABSTRACT  THOUGHT 

GREECE:  ARISTOTLE 

No  sooner  did  the  Greeks  turn  their  attention  to 
the  sciences  which  had  originated  in  Egypt  and 
Babylonia  than  the  characteristic  intellectual  qual- 
ity of  the  Hellenic  genius  revealed  itself.  Thales 
(640-546  B.C.),  who  is  usually  regarded  as  the  first 
of  the  Greek  philosophers,  was  the  founder  of  preek 
geometry  and  astronomy.  He  was  one  of  the  seven 
"wise  men"  of  Greece7  and  might  be  called  the 
Benjamin  Franklin  of  antiquity,  for  he  was  inter- 
ested in  commerce,  famous  for  political  sagacity,  and 
honored  for  his  disinterested  love  of  general  truth. 
His  birthplace  was  Miletus,  a  Greek  city  on  the 
coast  of  Asia  Minor.  There  is  evidence  that  he  ac- 
quired a  knowledge  of  Babylonian  astronomy.  The 
pursuit  of  commerce  carried  him  to  Egypt,  and  there 
he  gained  a  knowledge  of  geometry.  Not  only  so, 
but  he  was  able  to  advance  this  study  by  general- 
izing and  formulating  its  truths.  For  the  Egyptians, 
geometry  was  concerned  with  surfaces  and  dimen- 
sions, with  areas  and  cubical  contents ;  for  the  Greek, 
with  his  powers  of  abstraction,  it  became  a  study  of 
line  and  angle.  For  example,  Thales  saw  that  the 
angles  at  the  base  of  an  isosceles  triangle  are  equal, 
and  that  when  two  straight  lines  cut  one  another  the 
vertically  opposite  angles  are  equal.  However,  after 
having  established  general  principles,  he  showed  him- 


16          THE   HISTORY  OF   SCIENCE 

self  capable  of  applying  them  to  the  solution  of  par- 
ticular problems.  In  the  presence  of  the  Egyptian 
priests,  to  which  class  he  was  solely  indebted  for  in- 
struction, Thales  demonstrated  a  method  of  measur- 
ing the  height  of  a  pyramid  by  reference  to  its 
shadow.  And  again,  on  the  basis  of  his  knowledge 
of  the  relation  of  the  sides  of  a  triangle  to  its  angles, 
he  developed  a  practical  rule  for  ascertaining  the 
distance  of  a  ship  from  the  shore. 

The  philosophical  mind  of  Thales  laid  hold,  no 
doubt,  of  some  of  the  essentials  of  astronomical  sci- 
ence. The  particulars  usually  brought  forward  to 
prove  his  originality  tend  rather  to  show  his  indebt- 
edness to  the  Babylonians.  The  number  of  days  in 
the  year,  the  length  of  the  synodic  month,  the  rela- 
tion of  the  sun's  apparent  diameter  to  the  ecliptic, 
the  times  of  recurrence  of  eclipses,  were  matters  that 
had  long  been  known  to  the  Babylonians,  as  well  as 
to  the  Chinese.  However,  he  aroused  great  interest 
in  astronomy  among  the  Greeks  by  the  prediction 
of  a  solar  eclipse.  This  was  probably  the  eclipse  of 
585  B.C.,  which  interrupted  a  fierce  battle  between 
the  Medes  and  the  Lydians.  The  advice  of  Thales 
to  mariners  to  steer  by  the  Lesser  Bear,  as  nearer 
the  pole,  rather  than  by  the  Great  Bear,  shows  also 
that  in  his  astronomical  studies  as  in  his  geometri- 
cal he  was  not  indifferent  to  the  applications  of 
scientific  knowledge. 

In  fact,  some  writers  maintain  that  Thales  was 
not  a  philosopher  at  all,  but  rather  an  astronomer 
and  engineer.  We  know  very  little  of  his  purely 
speculative  thought.  We  do  know,  however,  that  he 
arrived  at  a  generalization  —  fantastic  to  most  minds 


INFLUENCE  OF  ABSTRACT  THOUGHT     17 

—  that  all  things  are  water.  Attempts  have  been 
made  to  add  to  this  statement,  and  to  explain  it 
away.  Its  great  interest  for  the  history  of  thought 
lies  in  the  fact  that  it  is  the  result  of  seeking  the 
constant  in  the  variable,  the  unitary  principle  in  the 
multiple  phenomena  of  nature.  This  abstract  and 
general  view  (though  perhaps  suggested  by  the 
Babylonian  belief  that  the  world  originated  in  a 
watery  chaos,  or  by  the  teaching  of  Egyptian  priests) 
was  preeminently  Greek,  and  was  the  first  of  a 
series  of  attempts  to  discover  the  basis  or  origin  of 
all  things.  One  of  the  followers  of  Thales  taught 
that  air  was  the  fundamental  principle ;  while  Her- 
aclitus,  anticipating  to  some  extent  modern  theories 
of  the  origin  of  the  cosmos,  declared  in  favor  of  a 
fiery  vapor  subject  to  ceaseless  change.  Empedo- 
cles,  the  great  philosopher-physician,  first  set  forth 
the  doctrine  of  the  four  elements  —  earth,  air,  fire, 
and  water.  For  Democritus  indivisible  particles  or 
atoms  are  fundamental  to  all  phenomena.  It  is  evi- 
dent that  the  theory  of  Thales  was  a  starting  point 
for  Greek  abstract  thought,  and  that  his  inclination 
to  seek  out  principles  and  general  laws  accounts  for 
his  influence  on  the  development  both  of  philosophy 
and  the  sciences. 

Pythagoras,  on  the  advice  of  Thales,  visited  Egypt 
in  the  pursuit  of  mathematics.  There  is  reason  to 
believe  that  he  also  visited  Babylonia.  For  him  and 
his  followers  mathematics  became  a  philosophy  — 
almost  a  religion.  They  had  discovered  (by  experi- 
menting with  the  inonochord,  the  first  piece  of 
physical-laboratory  apparatus,  consisting  of  a  tense 
harpstring  with  a  movable  bridge)  the  effect  on  the 


18          THE  HISTORY   OF   SCIENCE 

tone  of  the  string  of  a  musical  instrument  when  the 
length  is  reduced  by  one  half,  and  also  that  strings 
of  like  thickness  and  under  equal  tension  yield  har- 
monious tones  when  their  lengths  are  related  as 
1 :  2,  2 : 3,  3 : 4,  4 :  5.  The  Pythagoreans  drew  from 
this  the  extravagant  inference  that  the  heavenly 
bodies  would  be  in  distance  from  the  earth  as  1,  2, 
3,  4,  5,  etc.  Much  of  their  theory  must  seem  to  the 
modern  mind  merely  fanciful  and  unsupported  spec- 
ulation. At  the  same  time  it  is  only  just  to  this 
school  of  philosophers  to  recognize  that  their  assump- 
tion that  simple  mathematical  relationships  govern 
the  phenomena  of  nature  has  had  an  immense  influ- 
ence on  the  advance  of  the  sciences.  Whether  their 
fanaticism  for  number  was  owing  to  the  influence  of 
Egyptian  priests  or  had  an  Oriental  origin,  it  gave 
to  the  Pythagoreans  an  enthusiasm  for  pure  mathe- 
matics. They  disregarded  the  bearing  of  their  sci- 
ence on  the  practical  needs  of  life.  Old  problems 
like  squaring  the  circle,  trisecting  the  angle,  and 
doubling  the  cube,  were  now  attempted  in  a  new 
spirit  and  with  fresh  vigor.  The  first,  second,  and 
fourth  books  of  Euclid  are  largely  of  Pythagorean 
origin.  For  solid  geometry  as  a  science  we  are  also 
indebted  to  this  sect  of  number-worshipers.  One  of 
them  (Archytas,  428-347  B.C.,  a  friend  of  Plato) 
was  the  first  to  apply  geometry  to  mechanics.  We 
see  again  here,  as  in  the  case  of  Thales,  that  the 
love  of  abstract  thought,  the  pursuit  of  science  as 
science,  did  not  interfere  with  ultimate  practical 
applications. 

Plato  (429-347  B.C.),  like  many  other  Greek 
philosophers,    traveled    extensively,    visiting   Asia 


INFLUENCE  OF  ABSTRACT  THOUGHT     19 

Minor,  Egypt,  and  Lower  Italy,  where  Pythagorean 
influence  was  particularly  strong.  His  chief  interest 
lay  in  speculation.  For  him  there  were  two  worlds, 
the  world  of  sense  and  the  world  of  ideas.  The  senses 
deceive  us  ;  therefore,  the  philosopher  should  turn  his 
back  upon  the  world  of  sensible  impressions,  and 
develop^  the_reason.  In  his  Dialogues  he  outlined  a 
course  of  training  and  study,  the  professed  object  of 
which  was  to  educate  a  class  of  philosophers.  (Strange 
to  say,  Plato's  curriculum,  planned  originally  for  the 
intellectual  elite,  still  dictates  in  our  schools  the  edu- 
cation of  millions  of  boys  and  girls  whose  careers  do 
not  call  for  a  training  merely  of  the  reason.) 

Over  the  porch  of  his  school,  the  Academy  at 
Athens,  were  inscribed  the  words,  "  Let  no  one  who  is 
unacquainted  with  geometry  enter  here."  It  was  not 
because  it  was  useful  in  everyday  life  that  Plato  laid 
such  insistence  on  this  study,  but  because  it  increased 
the  students'  powers  of  abstraction  and  trained  the 
mind  to  correct  and  vigorous  thinking.  From  his 
point  of  view  the  chief  good  of  geometry  is  lost  unless 
we  can  through  it  withdraw  the  mind  from  the  par- 
ticular and  the  material.  He  delighted  in  clearness 
of  conception.  His  main  scientific  interest  was  in 
astronomy  and  mathematics.  We  owe  to  him  the 
definition  of  a  line  as  "  length  without  breadth,"  and 
the  formulation  of  the  axiom,  "  Equals  subtracted 
from  equals  leave  equals." 

Plato  had  an  immediate  influence  in  stimulating 
mathematical  studies,  and  has  been  called  a  maker 
of  mathematicians.  Euclid,  who  was  active  at  Alex- 
andria toward  the  end  of  the  fourth  century  B.C.,  was 
not  one  of  Plato's  immediate  disciples  but  shared  the 


20          THE  HISTORY  OF  SCIENCE 

great  philosopher's  point  of  view.  The  story  is  told 
that  one  of  his  pupils,  arrived  perhaps  at  the  pons 
asinorum,  asked,  "  What  do  I  get  by  learning  these 
things?"  Euclid,  calling  his  servant,  said,  "Give 
him  sixpence,  since  he  must  inake-^gain  out  of  what 
he  learns."  Adults  were  also  found,  even  among'the 
nimble-witted  Greeks,  to  whom  abstract  reasoning 
was  not  altogether  congenial.  This  is  attested  by  the 
familiar  story  of  Ptolemy,  King  of  Egypt,  who  once 
asked  Euclid  whether  geometry  could  not  be  learned 
in  some  easier  way  than  by  studying  the  geometer's 
book,  The  Elements.  To  this  the  schoolmaster  re- 
plied, "There  is  no  royal  road  to  geometry."  For 
the  academic  intelligence  abstract  and  abstruse 
mathematics  are  tonic  and  an  end  in  themselves.  As 
already  stated,  their  ultimate  practical  value  is  also 
immense.  One  of  Plato's  associates,  working  under 
his  direction,  investigated  the  curves  produced  by 
cutting  cones  of  different  kinds  in  a  certain  plane. 
These  curves  —  the  ellipse,  the  parabola,  hyperbola 
—  play  a  large  part  in  the  subsequent  history  of 
astronomy  and  mechanics.  Another  Platonist  made 
the  first  measurement  of  the  earth's  circumference. 
Aristotle,  the  greatest  pupil  of  Plato,  was  born  at 
Stagira  in  384  B.C.  He  came  of  a  family  of  physi- 
cians, was  trained  for  the  medical  profession,  and 
had  his  attention  early  directed  to  natural  phenomena. 
He  entered  the  Academy  at  Athens  about  367  B.C., 
and  studied  there  till  the  death  of  Plato  twenty 
years  later.  He  was  a  diligent  but,  as  was  natural, 
considering  the  character  of  his  early  education,  by 
no  means  a  passive  student.  Plato  said  that  Aristotle 
reacted  against  his  instructor  as  a  vigorous  colt  kicks 


INFLUENCE  OF  ABSTRACT  THOUGHT  21 

the  mother  that  nourishes  it.  The  physician's  son 
did  not  accept  without  modification  the  view  that  the 
philosopher  should  turn  his  back  upon  the  things  of 
sense.  He  had  been  trained  in  the  physical  science 
of  the  time,  and  believed  in  the  reality  of  concrete 
things.  At  the  same  time  he  absorbed  what  he  found 
of  value  in  his  master's  teachings.  He  thought  that 
science  did  not  consist  in  a  mere  study  of  individual 
things,  but  that  we  must  pass  on  to  a  formulation  of 
general  principles  and  then  return  to  a  study  of  the 
concrete.  His  was  a  great  systematizing  intellect, 
which  has  left  its  imprint  on  nearly  every  depart- 
ment of  knowledge.  Physical  astronomy,  physical 
geography,  meteorology,  physics,  chemistry,  geology, 
botany,  anatomy,  physiology,  embryology,  and  zool- 
ogy were  enriched  by  his  teaching.  It  was  through 
him  that  logic,  ethics,  psychology,  rhetoric,  aesthetics, 
political  science,  zoology  (especially  ichthyology), 
first  received  systematic  treatment.  As  a  great  mod- 
ern philosopher  has  said,  Aristotle  pressed  his  way 
through  the  mass  of  things  knowable,  and  subjected 
its  diversity  to  the  power  of  his  thought.  No  wonder 
that  for  ages  he  was  known  as  "  The  Philosopher," 
master  of  those  who  know.  His  purpose  was  to  com- 
prehend, to  define,  to  classify  the  phenomena  of  or- 
ganic and  inorganic  nature,  to  systematize  the  knowl- 
edge of  his  own  time. 

Twenty  years'  apprenticeship  in  the  school  of  Plato 
had  sharpened  his  logical  powers  and  added  to  his 
stock  of  general  ideas,  but  had  not  taught  him  to  dis- 
trust his  senses.  When  we  say  that  our  eyes  deceive 
us,  we  really  confess  that  we  have  misinterpreted  the 
data  that  our  sight  has  furnished.  Properly  to  know 


22  THE   HISTORY   OF   SCIENCE 

involves  the  right  use  of  the  senses  as  well  as  the 
right  use  of  reason.  The  advance  of  science  depends 
on  the  development  both  of  speculation  and  observa- 
tion. Aristotle  advised  investigators  to  make  sure  of 
the  facts  before  seeking  the  explanation  of  the  facts. 
Where  preconceived  theory  was  at  variance  with  ob- 
served facts,  the  former  must  of  course  give  way. 
Though  it  has  been  said  that  while  Plato  was  a 
dreamer,  Aristotle  was  a  thinker,  yet  it  must  be  ac- 
knowledged in  qualification  that  Plato  often  showed 
genuine  knowledge  of  natural  phenomena  in  anatomy 
and  other  departments  of  study,  and  that  Aristotle 
was  carried  away  at  times  by  his  own  presuppositions, 
or  failed  to  bring  his  theories  to  the  test  of  observa- 
tion. The  Stagirite  held  that  the  velocity  of  falling 
bodies  is  proportional  to  their  weight,  that  the  func- 
tion of  the  diaphragm  is  to  divide  the  region  of  the 
nobler  from  that  of  the  animal  passions,  and  that  the 
brain  is  intended  to  act  in  opposition  to  the  heart, 
the  brain  being  formed  of  earthy  and  watery  mate- 
rial, which  brings  about  a  cooling  effect.  The  theory 
of  the  four  elements  —  the  hot,  the  cold,  the  moist, 
the  dry  —  led  to  dogmatic  statements  with  little  at- 
tempt at  verification.  From  the  standpoint  of  modern 
studies  it  is  easy  to  point  out  the  mistakes  of  Aris- 
totle even.  Science  is  progressive,  not  infallible. 

In  his  own  time  he  was  rather  reproached  for  what 
was  considered  an  undignified  and  sordid  familiarity 
with  observed  facts.  His  critics  said  that  having 
squandered  his  patrimony,  he  had  served  in  the  army, 
and,  failing  there,  had  become  a  seller  of  drugs.  His 
observations  on  the  effects  of  heat  seem  to  have  been 
drawn  from  the  common  processes  of  the  home  and 


INFLUENCE  OF  ABSTRACT  THOUGHT     23 

the  workshop.  Even  in  the  ripening  of  fruits  heat  ap- 
pears to  him  to  have  a  cooking  effect.  Heat  distorts 
articles  made  of  potters'  clay  after  they  have  been 
hardened  by  cold.  Again  we  find  him  describing  the 
manufacture  of  potash  and  of  steel.  He  is  not  disdain- 
ful of  the  study  of  the  lower  animals,  but  invites  us 
to  investigate  all  forms  in  the  expectancy  of  discover- 
ing something  natural  and  beautiful.  In  a  similar 
spirit  of  scientific  curiosity  the  Aristotelian  work 
The,  rroll<  in*  studies  the.1  principle  of  the  lever,  the 
rudder,  the  wheel  and  axle,  the  forceps,  the  balance, 
the  beam,  the  wedge,  as  well  as  other  mechanical 
principles. 

In  Aristotle,  in  fact,  we  find  a  mind  exceptionally 
able  to  form  clear  ideas,  and  at  the  same  time  to 
observe  the  rich  variety  of  nature.  He  paid  homage 
both  to  the  multiplicity  and  the  uniformity  of  na- 
ture, the  wealth  of  the  phenomena  and  the  simplicity 
of  the  law  explaining  the  phenomena.  Many  general 
and  abstract  ideas  (category,  energy,  entomology, 
essence,  mean  between  extremes,  metaphysics,  me- 
teorology, motive,  natural  history,  principle,  syllo- 
gism) have  through  the  influence  of  Aristotle  become 
the  common  property  of  educated  people  the  world 
over. 

Plato  was  a  mathematician  and  an  astronomer. 
Aristotle  was  first  and  foremost  a  biologist.  His 
books  treated  the  history  of  animals,  the  parts  of 
animals,  the  locomotion  of  animals,  the  generation  of 
animals,  respiration,  life  and  death,  length  and  short- 
ness of  life,  youth  and  old  age.  His  psychology  is, 
like  that  of  the  present  day,  a  biological  psychology. 
In  his  contributions  to  biological  science  is  mani- 


24          THE   HISTORY  OF   SCIENCE 

fested  his  characteristic  inclination  to  be  at  once  ab- 
stract and  concrete.  His  works  display  a  knowledge 
of  over  five  hundred  living  forms.  He  dissected  speci- 
mens of  fifty  different  species  of  animals.  One  might 
mention  especially  his  minute  knowledge  of  the  sea- 
urchin,  of  the  murex  (source  of  the  famous  Tyrian 
dye),  of  the  chameleon,  of  the  habits  of  the  torpedo, 
the  so-called  fishing-frog,  and  nest-making  fishes,  as 
well  as  of  the  manner  of  reproduction  of  whales  and 
certain  species  of  sharks.  One  of  his  chief  contribu- 

>tions  to  anatomy  is  the  description  of  the  heart  and 
of  the  arrangement  of  the  blood-vessels.  A  repug- 
nance to  the  dissection  of  the  human  body  seems  to 
have  checked  to  some  extent  his  curiosity  in  refer- 
ence to  the  anatomy  of  man,  but  he  was  acquainted 
with  the  structure  of  the  internal  ear,  the  passage 
leading  from  the  pharynx  to  the  middle  ear,  and  the 
two  outer  membranes  of  the  brain  of  man.  Aristotle's 
genius  did  not  permit  him  to  get  lost  in  the  mere  de- 
tails of  observed  phenomena.  He  recognized  resem- 
blances and  differences  between  the  various  species, 
classified  animals  as  belonging  to  two  large  groups, 
distinguished  whales  and  dolphins  from  fishes,  recog- 
nized the  family  likeness  of  the  domestic  pigeon,  the 
wood  pigeon,  the  rock  pigeon,  and  the  turtle  dove. 
He  laid  down  the  characteristics  of  the  class  of  in- 
vertebrates to  which  octopus  and  sepia  belong.  Man 

^  takes  a  place  in  Aristotle's  system  of  nature  as  a 
social  animal,  the  highest  type  of  the  whole  series  of 
living  beings,  characterized  by  certain  powers  of  re- 
call, reason,  deliberation.  Of  course  it  was  not  to  be 
expected  that  Aristotle  should  work  out  a  fully  sat- 
isfactory classification  of  all  the  varieties  of  plants 


INFLUENCE  OF  ABSTRACT  THOUGHT    25 

and  animals  known  to  him.  Yet  his  purpose  and 
method  mark  him  as  the  father  of  natural  science. 
He  had  the  eye  to  observe  and  the  mind  to  grasp  the 
relationships  and  the  import  of  what  he  observed. 
His  attempt  to  classify  animals  according  to  the  na- 
ture of  their  teeth  (dentition)  has  been  criticized  as 
unsuccessful,  but  this  principle  of  classification  is  still 
of  use,  and  may  be  regarded  as  typical  of  his  mind, 
at  once  careful  and  comprehensive. 

One  instance  of  Aristotle's  combining  philosophi- 
cal speculation  with  acute  observation  of  natural 
phenomena  is  afforded  by  his  work  on  generation 
and  development.  He  knew  that  the  transmission  of 
life  deserves  special  study  as  the  predominant  func- 
tion of  the  various  species  of  plants  and  animals. 
Deformed  parents  may  have  well-formed  offspring. 
Children  may  resemble  grandparents  rather  than 
parents.  It  is  only  toward  the  close  of  its  develop- 
ment that  the  embryo  exhibits  the  characteristics  of 
its  parent  species.  Aristotle  traced  with  some  care 
the  embryological  development  of  the  chick  from 
the  fourth  day  of  incubation.  His  knowledge  of  the 
propagation  of  animals  was,  however,  not  sufficient  to 
make  him  reject  the  belief  in  spontaneous  generation 
from  mud,  sand,  foam,  and  dew.  His  errors  are 
readily  comprehensible,  as,  for  example,  in  attrib- 
uting spontaneous  generation  to  eels,  the  habits  and 
mode  of  reproduction  of  which  only  recent  studies 
have  made  fully  known.  In  regard  to  generation,  as 
in  other  scientific  fields,  the  philosophic  mind  of  Aris- 
totle anticipated  modern  theories,  and  also  raised 
general  questions  only  to  be  solved  by  later  investi- 
gation of  the  facts. 


26          THE   HISTORY   OF   SCIENCE 

Only  one  indication  need  be  given  of  the  practical 
results  that  flowed  from  Aristotle's  scientific  work. 
In  one  of  his  writings  he  has  stated  that  the  sphe- 
ricity of  the  earth  can  be  observed  from  the  fact  that 
its  shadow  on  the  moon  at  the  time  of  eclipse  is  an 
arc.  That  it  is  both  spherical  and  small  in  comparison 
with  the  heavenly  bodies  appears,  moreover,  from 
this,  that  stars  visible  in  Egypt  are  invisible  in  coun- 
tries farther  north  ;  while  stars  always  above  the 
horizon  in  northern  countries  are  seen  to  set  from 
countries  to  the  south.  Consequently  the  earth  is  not 
only  spherical  but  also  not  large ;  otherwise  this  phe- 
nomenon would  not  present  itself  on  so  limited  a 
change  of  position  on  the  part  of  the  observer.  "  It 
seems,  therefore,  not  incredible  that  the  region  about 
the  Pillars  of  Hercules  [Gibraltar]  is  connected  with 
that  of  India,  and  that  there  is  thus  only  one  ocean." 
It  is  known  that  this  passage  from  The  Philosopher 
influenced  Columbus  in  his  undertaking  to  reach  the 
Orient  by  sailing  west  from  the  coast  of  Spain. 

We  must  pass  over  Aristotle's  observation  of  a 
relationship  (homology)  between  the  arms  of  man, 
the  forelegs  of  quadrupeds,  the  wings  of  birds,  and 
the  pectoral  fins  of  fishes,  as  well  as  many  other 
truths  to  which  his  genius  for  generalization  led 
him. 

In  the  field  of  botany  Aristotle  had  a  wide 
knowledge  of  natural  phenomena,  and  raised  general 
questions  as  to  mode  of  propagation,  nourishment, 
relation  of  plants  to  animals,  etc.  His  pupil  and  life- 
long friend,  and  successor  as  leader  of  the  Peripa- 
tetic school  of  philosophy,  Theophrastus,  combined 
a  knowledge  of  mathematics,  astronomy,  botany,  and 


INFLUENCE  OF  ABSTRACT  THOUGHT  27 

mineralogy.  His  History  of  Plants  describes  about 
five  hundred  species.  At  the  same  time  he  treats 
the  general  principles  of  botany,  the  distribution  of 
plants,  the  nourishment  of  the  plant  through  leaf  as 
well  as  root,  the  sexuality  of  date  palm  and  terebinth. 
He  lays  great  stress  on  the  uses  of  plants.  His  classi- 
fication of  plants  is  inferior  to  Aristotle's  classifica- 
tion of  animals.  His  views  in  reference  to  spontaneous 
generation  are  more  guarded  than  those  of  his  master. 
His  work  On  Stones  is  dominated  by  the  practical 
rather  than  the  generalizing  spirit.  It  is  evidently 
inspired  by  a  knowledge  of  mines,  such  as  the  cele- 
brated Laurium,  from  which  Athens  drew  its  supply 
of  silver,  and  the  wealth  from  which  enabled  the 
Athenians  to  develop  a  sea-power  that  overmatched 
that  of  the  Persians.  Even  to-day  enough  remains  of 
the  galleries,  shafts,  scoria,  mine-lamps,  and  other 
utensils  to  give  a  clear  idea  of  this  scene  of  ancient 
industry.  Theophrastus  considered  the  medicinal 
uses  of  minerals  as  well  as  of  plants. 

"We  have  failed  to  mention  Hippocrates  (460-370 
B.C.),  the  Father  of  Medicine,  in  whom  is  found  an 
intimate  union  of  practical  science  and  speculative 
philosophy.  We  must  also  pass  over  such  later  Greek 
scientists  as  Aristarchus  and  Hipparchus  who  con- 
futed the  theories  of  Pythagoras  and  Plato  in  refer- 
ence to  the  relative  distances  of  the  heavenly  bodies 
from  the  earth.  Archimedes  of  Syracuse  demands, 
however,  particular  consideration.  He  lived  in  the 
third  century  B.C.,  and  has  been  called  the  greatest 
mathematician  of  antiquity.  In  him  we  find  the  de- 
votion to  the  abstract  that  marked  the  Greek  intelli- 
gence. He  went  so  far  as  to  say  that  every  kind  of 


28          THE   HISTORY   OF   SCIENCE 

art  is  ignoble  if  connected  with  daily  needs.  His  in- 
terest lay  in  abstruse  mathematical  problems.  His 
special  pride  was  in  having  determined  the  relative 
dimensions  of  the  sphere  and  the  enclosing  cylinder. 
He  worked  out  the  principle  of  the  lever.  "  Give 
me,"  he  said,  "  a  place  on  which  to  stand  and  I  will 
move  the  earth."  He  approximated  more  closely 
than  the  Egyptians  the  solution  of  the  problem  of 
the  relation  between  the  area  of  a  circle  and  the  ra- 
dius. His  work  had  practical  value  in  spite  of  him- 
self. At  the  request  of  his  friend  the  King  of  Sicily, 
he  applied  his  ingenuity  to  discover  whether  a  cer- 
tain crown  were  pure  gold  or  alloyed  with  silver,  and 
he  hit  upon  a  method  which  has  found  many  appli- 
cations in  the  industries.  His  name  is  associated 
with  the  endless  screw.  In  fact,  his  practical  contriv- 
ances won  such  repute  that  it  is  not  easy  to  separate 
the  historical  facts  from  the  legends  that  enshroud 
his  name.  He  aided  in  the  defense  of  his  native  city 
against  the  Romans  in  212  B.C.,  and  devised  war- 
engines  with  which  to  repel  the  besiegers.  After  the 
enemy  had  entered  the  city,  says  tradition,  he  stood 
absorbed  in  a  mathematical  problem  which  he  had 
diagrammed  on  the  sand.  As  a  rude  Roman  soldier 
approached,  Archimedes  cried,  "Don't  spoil  my  cir- 
cles," and  was  instantly  killed.  The  victorious  gen- 
eral, however,  buried  him  with  honor,  and  on  the 
tomb  of  the  mathematician  caused  to  be  inscribed 
the  sphere  with  its  enclosing  cylinder.  The  triumphs 
of  Greek  abstract  thought  teach  the  lesson  that  prac- 
tical men  should  pay  homage  to  speculation  even 
when  they  fail  to  comprehend  a  fraction  of  it. 


INFLUENCE  OF  ABSTRACT  THOUGHT    29 


REFERENCES 

Aristotle,  Historia  Animalium  ;  translated  by  D'A.  W.  Thomp- 
son. (Vol.  iv  of  the  Works  of  Aristotle  Translated  into  English. 
Oxford:  Clarendon  Press.) 

A.  B.  Buckley  (Mrs.  Buckley  Fisher),  A  Short  History  of  Natural 
Science. 

G.  H.  Lewes,  Aristotle  ;  A  Chapter  in  the  History  of  Science. 

T.  E.  Lones,  Aristotle's  Researches  in  Natural  Science. 

D'A.  W.  Thompson,  On  Aristotle  as  a  Biologist. 

William  Whewell,  History  of  the  Inductive  Sciences. 

Alfred  Weber,  History  of  Philosophy. 


CHAPTER  III 

SCIENTIFIC    THEORY    SUBORDINATED    TO 
APPLICATION  —  ROME  :  VITRUVIUS 

VITKUVIUS  was  a  cultured  engineer  and  architect. 
He  was  employed  in  the  service  of  the  Eoman  State 
at  the  time  of  Augustus,  shortly  before  the  begin- 
ning of  the  Christian  era.  He  planned  basilicas  and 
aqueducts,  and  designed  powerful  war-engines  capa- 
ble of  hurling  rocks  weighing  three  or  four  hundred 
pounds.  He  knew  the  arts  and  the  sciences,  held 
lofty  ideals  of  professional  conduct  and  dignity,  and 
was  a  diligent  student  of  Greek  philosophy. 

We  know  of  him  chiefly  from  his  ten  short  books 
on  Architecture  (De,  Architecture*,  Libri  Decem), 
in  which  he  touches  upon  much  of  the  learning  of 
his  time.  Architecture  for  Vitruvius  is  a  science 
arising  out  of  many  other  sciences.  Practice  and 
theory  are  its  parents.  The  merely  practical  man 
loses  much  by  not  knowing  the  background  of  his 
activities ;  the  mere  theorist  fails  by  mistaking  the 
shadow  for  the  substance.  Vitruvius  in  the  theoret- 
ical and  historical  parts  of  his  book  draws  largely 
on  Greek  writers ;  but  in  the  parts  bearing  on  prac- 
tice he  sets  forth,  with  considerable  shrewdness,  the 
outcome  of  years  of  thoughtful  professional  experi- 
ence. One  cannot  read  his  pages  without  feeling  that 
he  is  more  at  home  in  the  concrete  than  in  the  ab- 
stract and  speculative,  in  describing  a  catapult  than 
in  explaining  a  scientific  theory  or  a  philosophy.  He 


ROME:  VITRUVIUS  31 

was  not  a  Plato  or  an  Archimedes,  but  an  efficient 
officer  of  State,  conscious  of  indebtedness  to  the 
great  scientists  and  philosophers.  With  a  just  sense 
of  his  limitations  he  undertook  to  write,  not  as  a  lit- 
erary man,  but  as  an  architect.  His  education  had 
been  mainly  professional,  but,  the  whole  circle  of 
learning  being  one  harmonious  system,  he  had  been 
drawn  to  many  branches  of  knowledge  in  so  far  as 
they  were  related  to  his  calling. 

In  the  judgment  of  Vitruvius  an  architect  should 
be  a  good  writer,  able  to  give  a  lucid  explanation  of 
his  plans,  a  skillful  draftsman,  versed  in  geometry 
and  optics,  expert  at  figures,  acquainted  with  history, 
informed  in  the  principles  of  physics  and  of  ethics, 
knowing  something  of  music  (tones  and  acoustics), 
not  ignorant  of  law,  or  of  hygiene,  or  of  the  mo- 
tions, laws,  and  relations  to  each  other  of  the  heav- 
enly bodies.  For,  since  architecture  "  is  founded  upon 
and  adorned  with  so  many  different  sciences,  I  am 
of  opinion  that  those  who  have  not,  from  their  early 
youth,  gradually  climbed  up  to  the  summit,  cannot 
without  presumption,  call  themselves  masters  of  it." 

Vitruvius  was  far  from  sharing  the  view  of  Archi- 
medes that  art  which  was  connected  with  the  satis- 
faction of  daily  needs  was  necessarily  ignoble  and 
vulgar.  On  the  contrary,  his  interest  centered  in  the 
practical ;  and  he  was  mainly  concerned  with  scien- 
tific theory  by  reason  of  its  application  in  the  arts. 
Geometry  helped  him  plan  a  staircase ;  a  knowledge 
of  tones  was  necessary  in  discharging  catapults ;  law 
dealt  with  boundary-lines,  sewage-disposal,  and  con- 
tracts ;  hygiene  enabled  the  architect  to  show  a  Hip- 
pocratic  wisdom  in  the  choice  of  building-sites  with 


32          THE  HISTORY  OF  SCIENCE 

due  reference  to  airs  and  waters.  Vitruvius  had  the 
Roman  practical  and  regulative  genius,  not  the  ab- 
stract and  speculative  genius  of  Athens. 

The  second  book  begins  with  an  account  of  dif- 
ferent philosophical  views  concerning  the  origin  of 
matter,  and  a  discussion  of  the  earliest  dwellings  of 
man.  Its  real  theme,  however,  is  building-material 
—  brick,  sand,  lime,  stone,  concrete,  marble,  stucco, 
timber,  pozzolano.  In  reference  to  the  last  (vol- 
canic ash  combined  with  lime  and  rubble  to  form  a 
cement)  Vitruvius  writes  in  a  way  that  indicates  a 
discriminating  knowledge  of  geological  formations. 
Likewise  his  discussion  of  the  influence  of  the  Apen- 
nines on  the  rainfall,  and,  consequently,  on  the  tim- 
ber of  the  firs  on  the  east  and  west  of  the  range, 
shows  a  grasp  of  meteorological  principles.  His  real 
power  to  generalize  is  shown  in  connection  with  his 
specialty,  in  his  treatment  of  the  sources  of  build- 
ing-material, rather  than  in  his  consideration  of  the 
origin  of  matter. 

Similarly  the  fifth  book  begins  with  a  discussion 
of  the  theories  of  Pythagoras,  but  its  real  topic  is 
public  buildings  —  fora,  basilicas,  theaters,  baths, 
palaestras,  harbors,  and  quays.  In  the  theaters  bronze 
vases  of  various  sizes,  arranged  according  to  Pythag- 
orean musical  principles,  were  to  be  used  in  the 
auditorium  to  reinforce  the  voice  of  the  actor.  (This 
recommendation  was  misunderstood  centuries  later, 
when  Vitruvius  was  considered  of  great  authority, 
and  led  to  the  futile  practice  of  placing  earthenware 
jars  beneath  the  floors  of  church  choirs.)  According 
to  our  author,  "  The  voice  arises  from  flowing  breath, 
sensible  to  the  hearing  through  its  percussion  on 


ROME:  VITRUVIUS  33 

the  air."  It  is  compared  to  the  wavelets  produced  by 
a  stone  dropped  in  water,  only  that  in  the  case  of 
sound  the  waves  are  not  confined  to  one  plane.  This 
generalization  concerning  the  nature  of  sound  was 
probably  not  original,  however ;  it  may  have  been 
suggested  to  Vitruvius  by  one  of  the  Aristotelian 
writings. 

The  seventh  book  treats  of  interior  decoration  — 
mosaic  floors,  gypsum  mouldings,  wall  painting, 
white  lead,  red  lead,  verdigris,  mercury  (which  may 
be  used  to  recover  gold  from  worn-out  pieces  of  em- 
broidery), encaustic  painting  with  hot  wax,  colors 
(black,  blue,  genuine  and  imitation  murex  purple). 
The  eighth  book  deals  with  water  and  with  hydraulic 
engineering,  hot  springs,  mineral  waters,  leveling 
instruments,  construction  of  aqueducts,  lead  and 
clay  piping.  Vitruvius  was  not  ignorant  of  the  fact 
that  water  seeks  its  own  level,  and  he  even  argued 
that  air  must  have  weight  in  order  to  account  for 
the  rise  of  water  in  pumps.  In  his  time  it  was  more 
economical  to  convey  the  hard  water  by  aqueducts 
than  by  such  pipes  as  could  then  be  constructed. 
The  ninth  book  undertakes  to  rehearse  the  elements 
of  geometry  and  astronomy  —  the  signs  of  the  zodiac, 
the  sun,  moon,  planets,  the  phases  of  the  moon,  the 
mathematical  divisions  of  the  gnomon,  the  use  of  the 
sundial,  etc.  One  feels  in  reading  Vitruvius  that  his 
purpose  was  to  turn  to  practical  account  what  he  had 
gained  from  the  study  of  the  sciences ;  and,  at  the 
same  time,  one  is  convinced  that  his  applications  tend 
to  react  on  theoretical  knowledge,  and  lead  to  new 
insights  through  the  suggestion  of  new  problems. 

The  tenth  book  of  the  so-called  De  Architecture* 


34  THE  HISTORY  OF  SCIENCE 

is  concerned  with  machinery  —  windmills,  windlasses, 
axles,  pulleys,  cranes,  pumps,  fire-engines,  revolving 
spiral  tubes  for  raising  water,  wheels  for  irrigation 
worked  by  water-power,  wheels  to  register  distance 
traveled  by  land  or  water,  scaling-ladders,  batter- 
ing-rams, tortoises,  catapults,  scorpions,  and  ballistae. 
On  the  subject  of  war-engines  Vitruvius  speaks  with 
special  authority,  as  he  had  served,  probably  as  mili- 
tary engineer,  under  Julius  Caesar  in  46  B.C.,  and 
had  been  appointed  superintendent  of  ballistse  and 
other  military  engines  in  the  time  of  Augustus.  It 
was  to  the  divine  Emperor  that  his  book  was  dedi- 
cated as  a  protest  against  the  administration  of 
Roman  public  works.  In  its  pages  we  see  reflected 
the  life  of  a  nation  employed  in  conquering  and 
ruling  the  world,  with  a  genius  more  distinguished 
for  practical  achievement  than  for  theory  and  specu- 
lation. Its  author  is  truly  representative  of  Roman 
culture,  for  nearly  everything  that  Rome  had  of  a 
scientific  and  intellectual  sort  it  drew  from  Greece, 
and  it  selected  that  part  of  Greek  wisdom  that  minis- 
tered to  the  daily  needs  of  the  times.  In  his  work 
on  architecture,  Vitruvius  shows  himself  a  diligent 
and  devoted  student  of  the  sciences  in  order  that 
he  may  turn  them  to  account  in  his  own  department 
of  technology. 

If  you  glance  at  the  study  of  mathematics,  astron- 
omy, and  medicine  among  the  Romans  prior  to  the 
time  of  Greek  influence,  you  find  that  next  to  noth- 
ing had  been  accomplished.  Their  method  of  field 
measurement  was  far  less  developed  than  the  ancient 
Egyptian  geometry,  and  even  for  it  (as  well  as  for 
their  system  of  numerals)  they  were  indebted  to 


ROME:  VITRUVIUS  35 

the  Etruscans.  The  history  of  astronomy  has  nothing 
to  record  of  scientific  accomplishment  on  the  part  of 
the  Romans.  They  reckoned  time  by  months,  and  in 
the  earlier  period  kept  a  rude  tally  of  the  years  by 
driving  nails  into  a  statue  of  Janus,  the  ancient 
sun-god.  As  we  shall  see,  they  were  unable  to  regu- 
late the  calendar.  Again,  so  far  were  they  from  con- 
tributing to  the  development  of  medicine  that  they 
had  no  physicians  for  the  six  hundred  years  preced- 
ing the  coming  of  Greek  science.  A  medical  slave 
acted  as  overseer  of  the  family  health,  and  disease 
was  combated  in  primitive  fashion  by  prayers  and 
offerings  to  various  gods,  who  were  supposed  to  fur- 
nish general  health  or  to  influence  the  functions  of 
the  different  parts  of  the  body.  So  rude  was  the  na- 
tive culture  of  the  Romans  that  it  is  doubtful  whether 
they  had  any  schools  before  the  advent  of  Greek  learn- 
ing. The  girls  were  trained  by  their  mothers,  the 
boys  either  by  their  fathers  or  by  some  master  to 
whom  they  were  apprenticed. 

The  Greeks  were  conquered  by  the  Romans  in 
146  B.C.,  but  before  that  time  Roman  life  and  insti- 
tutions had  been  touched  by  Hellenic  culture.  Cato 
the  Censor  (who  died  in  149  B.C.)  and  other  con- 
servatives tried  in  vain  to  resist  the  invasion  of 
Greek  science,  philosophy,  and  refinement.  After  the 
conquest  of  Greece  the  master  became  pupil,  and 
the  conqueror  was  taken  captive.  The  Romans, 
however,  never  rose  to  preeminence  in  science  or  the 
fine  arts.  A  further  development  in  technology  cor- 
responded more  closely  to  their  national  needs,  and 
in  this  field  they  came  undoubtedly  to  surpass  the 
Greeks.  Bridges,  ships,  military  roads,  war-engines, 


36          THE  HISTORY  OF  SCIENCE 

aqueducts,  public  buildings,  organization  of  the 
State  and  the  army,  the  formulation  of  legal  proce- 
dure, the  enactment  and  codification  of  laws,  were 
necessary  to  secure  and  maintain  the  Empire.  The 
use  in  building  construction  of  a  knowledge  of  the 
right-angled  triangle  as  well  as  other  matters  known 
to  the  Egyptians  and  Babylonians,  and  Archimedes' 
method  of  determining  specific  gravity  were  of  pecul- 
iar interest  to  the  practical  Romans. 

Julius  Caesar,  102-44  B.C.,  instituted  a  reform  of 
the  calendar.  This  was  very  much  needed,  as  the 
Romans  were  eighty-five  days  out  of  their  reckoning, 
and  the  date  for  the  spring  equinox,  instead  of  com- 
ing at  the  proper  time,  was  falling  in  the  middle  of 
winter.  An  Alexandrian  astronomer  (Sosigenes)  as- 
sisted in  establishing  the  new  (Julian)  calendar.  The 
principle  followed  was  based  on  ancient  Egyptian 
practice.  Among  the  365  days  of  the  year  was  to 
be  inserted,  or  intercalated,  every  fourth  year  an 
extra  day.  This  the  Romans  did  by  giving  to  two 
days  in  leap-year  the  same  name  ;  thus  the  sixth  day 
before  the  first  of  March  was  repeated,  and  leap- 
year  was  known  as  a  bissextile  year.  Caesar,  trained 
himself  in  the  Greek  learning  and  known  to  his  con- 
temporaries as  a  writer  on  mathematics  and  astron- 
omy, also  planned  a  survey  of  the  Empire,  which  was 
finally  carried  into  execution  by  Augustus. 

There  is  evidence  that  the  need  of  technically 
trained  men  became  more  and  more  pressing  as  the 
Empire  developed.  At  first  there  were  no  special 
teachers  or  schools.  Later  we  find  mention  of  teach- 
ers of  architecture  and  mechanics.  Then  the  State 
came  to  provide  classrooms  for  technical  instruction 


ROME:  VITRUVIUS  37 

and  to  pay  the  salaries  of  the  teachers.  Finally, 
in  the  fourth  century  A.D.,  further  measures  were 
adopted  by  the  State.  The  Emperor  Constantino 
writes  to  one  of  his  officials  :  "  We  need  as  many  en- 
gineers as  possible.  Since  the  supply  is  small,  induce 
to  begin  this  study  youths  of  about  eighteen  years 
of  age  who  are  already  acquainted  with  the  sciences 
required  in  a  general  education.  Relieve  their  par- 
ents from  the  payment  of  taxes,  and  furnish  the  stu- 
dents with  ample  means." 

Pliny  the  Elder  (23-79  A.D.),  in  the  encyclopedic 
work  which  he  compiled  under  the  title  Natural 
History,  drew  freely  on  hundreds  of  Greek  and 
Latin  authors  for  his  facts  and  fables.  In  the  selec- 
tion that  he  made  from  his  sources  can  be  traced,  as 
in  the  work  of  Vitruvius  and  other  Latin  writers,  the 
tendency  to  make  the  sciences  subservient  to  the 
arts.  For  example,  the  one  thousand  species  of  plants 
of  which  he  makes  mention  are  considered  from  the 
medicinal  or  from  the  economic  point  of  view.  It  was 
largely  in  the  interest  of  their  practical  uses  that  the 
Roman  regarded  both  plants  and  animals ;  his  chief 
motive  was  not  a  disinterested  love  of  truth.  Pliny 
thought  that  each  plant  had  its  special  virtue,  and 
much  of  his  botany  is  applied  botany.  So  compre- 
hensive a  work  as  the  Natural  History  was  sure  to 
contain  interesting  anticipations  of  modern  science. 
Pliny  held  that  the  earth  hovers  in  the  heavens  up- 
held by  the  air,  that  its  sphericity  is  proved  by  the 
fact  that  the  mast  of  a  ship  approaching  the  land 
is  visible  before  the  hull  comes  in  sight.  He  also 
taught  that  there  are  inhabitants  on  the  other  side  of 
the  earth  (antipodes),  that  at  the  time  of  the  winter 


38  THE  HISTORY  OF  SCIENCE 

solstice  the  polar  night  must  last  for  twenty-four 
hours,  and  that  the  moon  plays  a  part  in  the  produc- 
tion of  the  tides.  Nevertheless,  the  whole  book  is 
permeated  by  the  idea  that  the  purpose  of  nature  is 
to  minister  to  the  needs  of  man. 

It  further  marks  the  practical  spirit  among  the 
Romans  that  a  work  on  agriculture  by  a  Carthagin- 
ian (Mago)  was  translated  by  order  of  the  Senate. 
Cato  (234-149  B.C.),  so  characteristically  Roman 
in  his  genius,  wrote  (JDe  Re  Rustica)  concerning 
grains  and  the  cultivation  of  fruits.  Columella  wrote 
treatises  on  agriculture  and  forestry.  Among  the 
technical  writings  of  Varro  besides  the  book  on  agri- 
culture, which  is  extant,  are  numbered  works  on 
law,  mensuration,  and  naval  tactics. 

It  was  but  natural  that  at  the  time  of  the  Roman 
Empire  there  should  be  great  advances  in  medical 
science.  A  Roman's  interest  in  a  science  was  keen 
when  it  could  be  proved  to  have  immediate  bearing 
on  practical  life.  The  greatest  physician  of  the  time, 
however,  was  a  Greek.  Galen  (131-201  A.D.),  who 
counted  himself  a  disciple  of  Hippocrates,  began  to 
practice  at  Rome  at  the  age  of  thirty-three.  He  was 
the  only  experimental  physiologist  before  the  time 
of  Harvey.  He  studied  the  vocal  apparatus  in  the 
larynx,  and  understood  the  contraction  and  relax- 
ation of  the  muscles,  and,  to  a  considerable  extent, 
the  motion  of  the  blood  through  the  heart,  lungs,  and 
other  parts  of  the  body.  He  was  a  vivisector,  made 
sections  of  the  brain  in  order  to  determine  the  func- 
tions of  its  parts,  and  severed  the  gustatory,  optic, 
and  auditory  nerves  with  a  similar  end  in  view.  His 
dissections  were  confined  to  the  lower  animals.  Yet 


ROME:  VITRUVIUS  39 

his  works  on  human  anatomy  and  physiology  were 
authoritative  for  the  subsequent  thirteen  centuries. 
It  is  difficult  to  say  how  much  of  the  work  and 
credit  of  this  practical  scientist  is  to  be  given  to  the 
race  from  which  he  sprang  and  how  much  to  the 
social  environment  of  his  professional  career.  (In 
the  ruins  of  Pompeii,  destroyed  in  79  A.D.,  have 
been  recovered  some  two  hundred  kinds  of  surgical 
instrument,  and  in  the  later  Empire  certain  depart- 
ments of  surgery  developed  to  a  degree  not  sur- 
passed till  the  sixteenth  century.)  If  it  is  too  much 
to  say  that  the  Roman  environment  is  responsible 
for  Galen's  achievements,  we  can  at  least  say  that 
it  was  characteristic  of  the  Roman  people  to  wel- 
come such  science  as  his,  capable  of  demonstrating 
its  utility. 

Dioscorides  was  also  a  Greek  who,  long  resident 
at  Rome,  applied  his  science  in  practice.  He  knew 
six  hundred  different  plants,  one  hundred  more  than 
Theophrastus.  The  latter  laid  much  stress,  as  we  have 
seen  in  the  preceding  chapter,  on  the  medicinal  prop- 
erties of  plants,  but  in  this  respect  he  was  outdone 
by  Dioscorides  (as  well  as  by  Pliny).  Theophrastus 
was  the  founder  of  the  science  of  botany,  Dioscor- 
ides the  founder  of  materia  medica. 

Quintilian,  born  in  Spain,  spent  the  greater  part 
of  his  life  as  a  teacher  of  rhetoric  in  Rome.  He  val- 
ued the  sciences,  not  on  their  own  account,  but  as  they 
might  subserve  the  purposes  of  the  orator.  Music, 
astronomy,  logic,  and  even  theology,  might  be  ex- 
ploited as  aids  to  public  speech.  In  the  time  of  Quin- 
tilian (first  century  A.D.),  as  in  our  own,  oratory  was 
considered  one  of  the  great  factors  in  a  young  man's 


40          THE  HISTORY  OF  SCIENCE 

success ;  mock  debating  contests  were  frequent,  and 
the  periods  of  the  future  orators  reverberated  among 
the  seven  hills  of  Rome.  To  him  our  schools  are  also 
indebted  for  the  method  of  teaching  foreign  languages 
by  declensions,  conjugations,  vocabularies,  formal 
rhetoric  and  annotations.  He  considered  ethics  the 
most  valuable  part  of  philosophy. 

In  fact,  it  would  not  be  pressing  our  argument  un- 
duly to  say  that,  so  far  as  the  minds  of  the  Romans 
turned  to  speculation,  it  was  the  tendency  to  practi- 
cal philosophy  —  Epicureanism  or  Stoicism  —  that 
was  most  characteristic.  This  was  true  even  of  Lu- 
cretius (98-55  B.C.),  author  of  the  noble  poem  con- 
cerning the  Nature  of  Things  (De  Rerum  Natura). 
In  this  work  he  writes  under  the  inspiration  of  Greek 
philosophy.  His  model  was  a  poem  by  Empedocles 
on  Nature,  the  grand  hexameters  of  which  had  fasci- 
nated the  Roman  poet.  The  distinctive  feature  of  the 
work  of  Lucretius  is  the  purpose,  ethical  rather  than 
speculative,  to  curb  the  ambition,  passion,  luxury  of 
those  hard  pagan  times,  and  likewise  to  free  the  souls 
of  his  countrymen  from  the  fear  of  the  gods  and  the 
fear  of  death,  and  to  replace  superstition  by  peace  of 
mind  and  purity  of  heart. 

From  the  work  on  Physical  Science  (  Qucestionum 
Naturalium,  Libri  Septem)  of  Seneca,  the  tutor  of 
Nero,  we  learn  that  the  Romans  made  use  of  globes 
filled  with  water  as  magnifiers,  employed  hothouses 
in  their  highly  developed  horticulture,  and  observed 
the  refraction  of  colors  by  the  prism.  At  the  same 
time  the  book  contains  interesting  conjectures  in 
reference  to  the  relation  of  earthquakes  and  vol- 
canoes, and  to  the  fact  that  comets  travel  in  fixed 


ROME:  VITRUVIUS  41 

orbits.  In  the  main,  however,  this  work  is  an  attempt 
to  find  a  basis  for  ethics  in  natural  phenomena.  Sen- 
eca was  a  Stoic,  as  Lucretius  was  an  Epicurean, 
moralist. 

When  we  glance  back  at  the  culture,  or  cultures, 
of  the  great  peoples  of  antiquity,  Egyptian,  Baby- 
lonian, Greek,  and  Roman,  that  which  had  its  center 
on  the  banks  of  the  Tiber  offers  the  closest  analogy 
to  our  own.  Among  English-speaking  peoples  as 
among  the  Romans  there  is  noticeable  a  certain  con- 
tempt for  scientific  studies  strangely  mingled  with 
an  inclination  to  exploit  all  theory  in  the  interest  of 
immediate  application.  An  English  author,  writing 
in  1834,  remarks  that  the  Romans,  eminent  in  war, 
in  polite  literature,  and  civil  policy,  showed  at  all 
times  a  remarkable  indisposition  to  the  pursuit  of 
mathematical  and  physical  science.  Geometry  and 
astronomy,  so  highly  esteemed  by  the  Greeks,  were 
not  merely  disregarded  by  the  Italians,  but  even  con- 
sidered beneath  the  attention  of  a  man  of  good  birth 
and  liberal  education ;  they  were  imagined  to  partake 
of  a  mechanical,  and  therefore  servile,  character.  "  The 
results  were  seen  to  be  made  use  of  by  the  mechani- 
cal artist,  and  the  abstract  principles  were  therefore 
supposed  to  be,  as  it  were,  contaminated  by  his  touch. 
This  unfortunate  peculiarity  in  the  taste  of  his  coun- 
trymen is  remarked  by  Cicero.  And  it  may  not  be 
irrelevant  to  inquire,  whether  similar  prejudices  do 
not  prevail  to  some  extent  even  among  ourselves." 
To  Americans  also  must  be  attributed  an  impatience 
of  theory  as  theory,  and  a  predominant  interest  hi  the 
applications  of  science. 


42  THE  HISTORY  OF  SCIENCE 


REFERENCES 

Lucretius,  The  Nature  of  Things  ;  translated  by  H.  A.  J.  Munro. 
Pliny,  Natural  History  ;  translated  by  Philemon  Holland. 
Professor  Baden  Powell,  History  of  Natural  Philosophy. 
Seneca,  Physcial  Science  ;  translated  by  John  Clarke. 
Vitruvius,  Architecture  ;  translated  by  Joseph  Gwilt,  1826. 
Vitruvius,  Architecture  ;  translated  by  Professor  M.  H.  Morgan, 
1914. 


CHAPTER  IV 

THE    CONTINUITY  OF  SCIENCE THE  MEDIEVAL 

CHURCH   AND    THE   ARABS 

LEARNING  has  very  often  and  very  aptly  been 
compared  to  a  torch  passed  from  hand  to  hand.  By 
the  written  sign  or  spoken  word  it  is  transmitted 
from  one  person  to  another.  Very  little  advance  in 
culture  could  be  made  even  by  the  greatest  man  of 
genius  if  he  were  dependent,  for  what  knowledge  he 
might  acquire,  merely  on  his  own  personal  observa- 
tion. Indeed,  it  might  be  said  that  exceptional  men- 
tal ability  involves  a  power  to  absorb  the  ideas  of 
others,  and  even  that  the  most  original  people  are 
those  who  are  able  to  borrow  the  most  freely. 

In  recalling  the  lives  of  certain  great  men  we  may 
at  first  be  inclined  to  doubt  this  truth.  How  shall 
we  account  for  the  part  played  in  the  progress  of 
civilization  by  the  rustic  Burns,  the  village-bred 
Shakespeare,  or  by  Lincoln  the  frontiersman?  When, 
however,  we  scrutinize  the  case  of  any  one  of  these, 
we  discover,  of  course,  exceptional  natural  endow- 
ment, susceptibility  to  mental  influence,  remarkable 
powers  of  acquisition,  but  no  ability  to  produce  any- 
thing absolutely  original.  In  the  case  of  Lincoln, 
for  example,  we  find  that  in  his  youth  he  was  as 
distinguished  by  diligence  in  study  as  by  physical 
stature  and  prowess.  After  he  withdrew  from 
school,  he  read,  wrote,  and  ciphered  (in  the  inter- 
vals of  manual  work)  almost  incessantly.  He  read 


44          THE  HISTORY  OF  SCIENCE 

everything  he  could  lay  hands  on.  He  copied  out 
what  most  appealed  to  him.  A  few  books  he  read 
and  re-read  till  he  had  almost  memorized  them. 
What  constituted  his  library  ?  The  Bible,  ^Esop's 
Fables,  Robinson  Crusoe,  The  Pilgrim's  Progress, 
a  Life  of  Washington,  a  History  of  the  United 
States.  These  established  for  him  a  vital  relation 
with  the  past,  and  laid  the  foundations  of  a  demo- 
cratic culture ;  not  the  culture  of  a  Chesterfield,  to 
be  sure,  but  something  immeasurably  better,  and 
none  the  less  good  for  being  almost  universally  ac- 
cessible. Lincoln  developed  his  logical  powers  con- 
ning the  dictionary.  Long  before  he  undertook  the 
regular  study  of  the  law,  he  spent  long  hours  poring 
over  the  revised  statutes  of  the  State  in  which  he 
was  living.  From  a  book  he  mastered  with  a  pur- 
pose the  principles  of  grammar.  In  the  same  spirit 
he  learned  surveying,  also  by  means  of  a  book. 
There  is  no  need  to  ignore  any  of  the  influences 
that  told  toward  the  development  of  this  great 
statesman,  the  greatest  of  English-speaking  orators, 
but  it  is  evident  that  remote  as  was  his  habitation 
from  all  the  famous  centers  of  learning  he  was,  never- 
theless, early  immersed  in  the  current  of  the  world's 
best  thought. 

Similarly,  in  the  history  of  science,  every  great 
thinker  has  his  intellectual  pedigree.  Aristotle  was 
the  pupil  of  Plato,  Plato  was  the  disciple  of  Soc- 
rates, and  the  latter's  intellectual  genealogy  in  turn 
can  readily  be  traced  to  Thales,  and  beyond  —  to 
Egyptian  priests  and  Babylonian  astronomers. 

The  city  of  Alexandria,  founded  by  the  pupil  of 
Aristotle  in  332  B.C.,  succeeded  Athens  as  the  center 


THE  CONTINUITY  OF  SCIENCE       45 

of  Greek  culture.  On  the  death  of  Alexander  the 
Great,  Egypt  was  ruled  by  one  of  his  generals, 
Ptolemy,  who  assumed  the  title  of  king.  This  mon- 
arch, though  often  engaged  in  war,  found  time  to 
encourage  learning,  and  drew  to  his  capital  scholars 
and  philosophers  from  Greece  and  other  countries. 
He  wrote  himself  a  history  of  Alexander's  cam- 
paigns, and  instituted  the  famous  library  of  Alexan- 
dria. This  was  greatly  developed  (and  supplemented 
with  schools  of  science  and  an  observatory)  by  his 
son  Ptolemy  Philadelphus,  a  prince  distinguished  by 
his  zeal  in  promoting  the  good  of  the  human  species. 
He  collected  vast  numbers  of  manuscripts,  had 
strange  animals  brought  from  distant  lands  to  Alex- 
andria, and  otherwise  promoted  scientific  research. 
This  movement  was  continued  under  Ptolemy  III 
(246-221  B.C.). 

Something  has  already  been  said  of  the  early  as- 
tronomers and  mathematicians  of  Alexandria.  The 
scientific  movement  of  the  later  Alexandrian  period 
found  its  consummation  in  the  geographer,  astrono- 
mer, and  mathematician  Claudius  Ptolemy  (not  to 
be  confused  with  the  rulers  of  that  name).  He  was 
most  active  127-151  A.D.,  and  is  best  known  by  his 
work  the  Syntaxis,  which  summarized  what  was 
known  in  astronomy  at  that  time.  Ptolemy  drew  up 
a  catalogue  of  1080  stars  based  on  the  earlier  work 
of  Hipparchus.  He  followed  that  astronomer  in 
teaching  that  the  earth  is  the  center  of  the  move- 
ment of  the  heavenly  bodies,  and  this  geocentric 
system  of  the  heavens  became  known  as  the  Ptole- 
maic system  of  astronomy.  To  Hipparchus  and 
Ptolemy  we  owe  also  the  beginnings  of  the  science 


46  THE  HISTORY  OF  SCIENCE 

of  trigonometry.  The  Syntaxis  sets  forth  his  method 
of  drawing  up  a  table  of  chords.  For  example,  the 
side  of  a  hexagon  inscribed  in  a  circle  is  equal  to 
the  radius,  and  is  the  chord  of  60°,  or  of  the  sixth 
part  of  the  circle.  The  radius  is  divided  into  sixty 
equal  parts,  and  these  again  divided  and  subdivided 
sexagesimally.  The  smaller  divisions  and  the  sub- 
divisions are  known  as  prime  minute  parts  and  sec- 
ond minute  parts  (paries  minutes  primce  and  partes 
minutce  secundce),  whence  our  terms  "  minute  "  and 
"  second."  The  sexagesimal  method  of  dividing  the 
circle  and  its  parts  was,  as  we  have  seen  in  the  first 
chapter,  of  Babylonian  origin. 

Ptolemy  was  the  last  of  the  great  Greek  astrono- 
mers. In  the  fourth  century  and  at  the  beginning 
of  the  fifth,  Theon  and  his  illustrious  daughter  Hy- 
patia  commented  on  and  taught  the  astronomy  of 
Ptolemy.  In  the  Greek  schools  of  philosophy  Plato's 
doctrine  of  the  supreme  reality  of  the  invisible  world 
was  harmonized  for  a  time  with  Christian  mysticism, 
but  these  schools  were  suppressed  at  the  beginning 
of  the  sixth  century.  The  extinction  of  scientific  and 
of  all  other  learning  seemed  imminent. 

What  were  the  causes  of  this  threatened  break  in 
the  historical  continuity  of  science  ?  They  were  too 
many  and  too  varied  to  admit  of  adequate  statement 
here.  From  the  latter  part  of  the  fourth  century  the 
Roman  Empire  had  been  overrun  by  the  Visigoths, 
the  Vandals,  the  Huns,  the  Ostrogoths,  the  Lom- 
bards, and  other  barbarians.  Even  before  these  incur- 
sions learning  had  suffered  under  the  calamity  of 
war.  In  the  time  of  Julius  Caesar  the  larger  of  the 
famous  libraries  of  Alexandria,  containing,  it  is  com- 


THE  CONTINUITY  OF  SCIENCE       47 

puted,  some  490,000  rolls,  caught  fire  from  ships 
burning  in  the  harbor,  and  perished.  This  alone 
involved  an  incalculable  setback  to  the  march  of 
scientific  thought. 

.  Another  influence  tending  to  check  the  advance  of 
the  sciences  was  the  clash  between  Christian  and  Pagan 
ideals.  To  many  of  the  bishops  of  the  Church  the  aims 
and  pursuits  of  science  seemed  vain  and  trivial  when 
compared  with  the  preservation  of  purity  of  charac- 
ter or  the  assurance  of  eternal  felicity.  Many  were 
convinced  that  the  end  of  the  world  was  at  hand, 
and  strove  to  fix  their  thoughts  solely  on  the  world 
to  come.  Their  austere  disregard  of  this  life  found 
some  support  in  a  noble  teaching  of  the  Stoic  phi- 
losophy that  death  itself  is  no  evil  to  the  just  man. 
The  early  Christian  teachers  held  that  the  body 
should  be  mortified  if  it  interfered  with  spiritual 
welfare.  Disease  is  a  punishment,  or  a  discipline  to 
be  patiently  borne.  One  should  choose  physical  un- 
cleanliness  rather  than  run  any  risk  of  moral  con- 
tamination. It  is  not  impossible  for  enlightened 
people  at  the  present  time  to  assume  a  tolerant  atti- 
tude toward  the  worldly  Greeks  or  the  other-worldly 
Christians.  At  that  time,  however,  mutual  antipathy 
was  intense.  The  long  and  cruel  war  between  science 
and  Christian  theology  had  begun. 

Not  all  the  Christian  bishops,  to  be  sure,  took  a 
hostile  view  of  Greek  learning.  Some  regarded  the 
great  philosophers  as  the  allies  of  the  Church.  Some 
held  that  churchmen  should  study  the  wisdom  of  the 
Greeks  in  order  the  better  to  refute  them.  Others 
held  that  the  investigation  of  truth  was  no  longer 
necessary  after  mankind  had  received  the  revelation 


48          THE  HISTORY  OF  SCIENCE 

of  the  gospel.  One  of  the  ablest  of  the  Church  Fa- 
thers regretted  his  early  education  and  said  that  it 
would  have  been  better  for  him  if  he  had  never  heard  of 
Democritus.  The  Christian  writer  Lactantius  asked 
shrewdly  whence  atoms  came,  and  what  proof  there 
was  of  their  existence.  He  also  allowed  himself  to 
ridicule  the  idea  of  the  antipodes,  a  topsy-turvy 
world  of  unimaginable  disorder.  In  389  A.D.  one  of 
the  libraries  at  Alexandria  was  destroyed  and  its 
books  were  pillaged  by  the  Christians.  In  415 
Hypatia,  Greek  philosopher  and  mathematician,  was 
murdered  by  a  Christian  mob.  In  642  the  Arabs 
having  pushed  their  conquest  into  northern  Africa 
gained  possession  of  Alexandria.  The  cause  of  learn- 
ing seemed  finally  and  irrecoverably  lost. 

The  Arab  conquerors,  however,  showed  themselves 
singularly  hospitable  to  the  culture  of  the  nations 
over  which  they  had  gained  control.  Since  the  time 
of  Alexander  there  had  been  many  Greek  settlers  in 
the  larger  cities  of  Syria  and  Persia,  and  here  learn- 
ing had  been  maintained  in  the  schools  of  the  Jews 
and  of  a  sect  of  Christians  (Nestorians),  who  were 
particularly  active  as  educators  from  the  fifth  century 
to  the  eleventh.  The  principal  Greek  works  on  sci- 
ence had  been  translated  into  Syrian.  Hindu  arith- 
metic and  astronomy  had  found  their  way  into  Persia. 
By  the  ninth  century  all  these  sources  of  scientific 
knowledge  had  been  appropriated  by  the  Arabs. 
Some  fanatics  among  them,  to  be  sure,  held  that 
one  book,  the  Koran,  was  of  itself  sufficient  to  in- 
sure the  well-being  of  the  whole  human  race,  but 
happily  a  more  enlightened  view  prevailed. 

In  the  time  of  Harun  Al-Rashid  (800  A.D.),  and 


THE  CONTINUITY  OF  SCIENCE       49 

his  son,  the  Caliphate  of  Bagdad  was  the  center 
of  Arab  science.  Mathematics  and  astronomy  were 
especially  cultivated ;  an  observatory  was  established ; 
and  the  work  of  translation  was  systematically  car- 
ried on  by  a  sort  of  institute  of  translators,  who  ren- 
dered the  writings  of  Aristotle,  Hippocrates,  Galen, 
Euclid,  Ptolemy,  and  other  Greek  scientists,  into  Ara- 
bic. The  names  of  the  great  Arab  astronomers  and 
mathematicians  are  not  popularly  known  to  us ;  their 
influence  is  greater  than  their  fame.  One  of  them 
describes  the  method  pursued  by  him  in  the  ninth 
century  in  taking  measure  of  the  circumference  of 
the  earth.  A  second  developed  a  trigonometry  of 
sines  to  replace  the  Ptolemaic  trigonometry  of  chords. 
A  third  made  use  of  the  so-called  Arabic  (really 
Hindu)  system  of  numerals,  and  wrote  the  first  work 
on  Algebra  under  that  name.  In  this  the  writer  did 
not  aim  at  the  mental  discipline  of  students,  but 
sought  to  confine  himself  to  what  is  easiest  and  most 
useful  in  calculation,  "  such  as  men  constantly  re- 
quire in  cases  of  inheritance,  legacies,  partition,  law- 
suits, and  trade,  and  in  all  their  dealings  with  one 
another,  or  where  the  measuring  of  lands,  the  dig- 
ging of  canals,  geometrical  computation,  and  other 
objects  of  various  sorts  and  kinds  are  concerned." 

In  the  following  centuries  Arab  institutions  of 
higher  learning  were  widely  distributed  and  the  flood- 
tide  of  Arab  science  was  borne  farther  west.  At 
Cairo  about  the  close  of  the  tenth  century  the  first 
accurate  records  of  eclipses  were  made,  and  tables 
were  constructed  of  the  motions  of  the  sun,  moon, 
and  planets.  Here  as  elsewhere  the  Arabs  displayed 
ingenuity  in  the  making  of  scientific  apparatus,  celes- 


50  THE  HISTORY  OF  SCIENCE 

tial  globes,  sextants  of  large  size,  quadrants  of  vari- 
ous sorts,  and  contrivances  from  which  in  the  course 
of  time  were  developed  modern  surveying  instruments 
for  measuring  horizontal  and  vertical  angles.  Before 
the  end  of  the  eleventh  century  an  Arab  born  at 
Cordova,  the  capital  of  Moorish  Spain,  constructed 
the  Toletan  Tables.  These  were  followed  in  1252 
by  the  publication  of  the  Alphonsine  Tables,  an 
event  which  astronomers  regard  as  marking  the 
dawn  of  European  science. 

Physics  and  chemistry,  as  well  as  mathematics  and 
astronomy,  owe  much  in  their  development  to  the 
Arabs.  An  Arabian  scientist  of  the  eleventh  century 
studied  the  phenomena  of  the  reflection  and  refrac- 
tion of  light,  explained  the  causes  of  morning  and 
evening  twilight,  understood  the  magnifying  power 
of  lenses  and  the  anatomy  of  the  human  eye.  Our 
use  of  the  terms  retina,  cornea,  and  vitreous  humor 
may  be  traced  to  the  translation  of  his  work  on  op- 
tics. The  Arabs  also  made  fair  approximations  to 
the  correct  specific  weights  of  gold,  copper,  mercury, 
and  lead.  Their  alchemy  was  closely  associated  with 
metallurgy,  the  making  of  alloys  and  amalgams,  and 
the  handicrafts  of  the  goldsmiths  and  silversmiths. 
The  alchemists  sought  to  discover  processes  whereby 
one  metal  might  be  transmuted  into  another.  Sul- 
phur affected  the  color  and  substance.  Mercury  was 
supposed  to  play  an  important  part  in  metal  trans- 
mutations. They  thought,  for  example,  that  tin  con- 
tained more  mercury  than  lead,  and  that  the  baser, 
more  unhealthy  metal  might  be  converted  into  the 
nobler  and  more  healthy  by  the  addition  of  mercury. 
They  even  sought  for  a  substance  that  might  effect 


THE  CONTINUITY  OF  SCIENCE       51 

all  transmutations,  and  be  for  mankind  a  cure  for 
all  ailments,  even  that  of  growing  old.  The  writings 
that  have  been  attributed  to  Geber  show  the  advances 
that  chemistry  made  through  the  experiments  of  the 
Arabs.  They  produced  sulphuric  and  nitric  acids, 
and  aqua  regia,  able  to  dissolve  gold,  the  king  of 
metals.  They  could  make  use  of  wet  methods,  and 
form  metallic  salts  such  as  silver  nitrate.  Labora- 
tory processes  like  distilling,  filtering,  crystallization, 
sublimation,  became  known  to  the  Europeans  through 
them.  They  obtained  potash  from  wine  lees,  soda 
from  sea-plants,  and  from  quicksilver  the  mercuric 
oxide  which  played  so  interesting  a  part  in  the  later 
history  of  chemistry. 

Much  of  the  science  lore  of  the  Arabs  arose  from 
their  extensive  trade,  and  in  the  practice  of  medi- 
cine. They  introduced  sugar-cane  into  Europe,  im- 
proved the  methods  of  manufacturing  paper,  discov- 
ered a  method  of  obtaining  alcohol,  knew  the  uses 
of  gypsum  and  of  white  arsenic,  were  expert  in 
pharmacy  and  learned  in  materia  medica.  They  are 
sometimes  credited  with  introducing  to  the  West  the 
knowledge  of  the  mariner's  compass  and  of  gun- 
powder. 

Avicenna  (980-1037),  the  Arab  physician,  not 
only  wrote  a  large  work  on  medicine  (the  Canwi) 
based  on  the  lore  of  Galen,  which  was  used  as  a  text- 
book for  centuries  in  the  universities  of  Europe,  but 
wrote  commentaries  on  all  the  works  of  Aristotle. 
For  Averroes  (1126-1198),  the  Arab  physician  and 
philosopher,  was  reserved  the  title  "  The  Commen- 
tator," due  to  his  devotion  to  the  works  of  the  Greek 
biologist  and  philosopher.  It  was  through  the  com- 


52          THE  HISTORY  OF  SCIENCE 

mentaries  of  Averroes  that  Aristotelian  science  be- 
came known  in  Europe  during  the  Middle  Ages.  In 
his  view  Aristotle  was  the  founder  and  perfecter  of 
science ;  yet  he  showed  an  independent  knowledge  of 
physics  and  chemistry,  and  wrote  on  astronomy  and 
medicine  as  well  as  philosophy.  He  set  forth  the 
facts  in  reference  to  natural  phenomena  purely  in 
the  interests  of  the  truth.  He  could  not  conceive  of 
anything  being  created  from  nothing.  At  the  same 
time  he  taught  that  God  is  the  essence,  the  eternal 
cause,  of  progress.  It  is  in  humanity  that  intellect 
most  clearly  reveals  itself,  but  there  is  a  transcend- 
ent intellect  beyond,  union  with  which  is  the  highest 
bliss  of  the  individual  soul.  With  the  death  of  the 
Commentator  the  culture  of  liberal  science  among 
the  Arabs  came  to  an  end,  but  his  influence  (and 
through  him  that  of  Aristotle)  was  perpetuated  in  all 
the  western  centers  of  education. 

The  preservation  of  the  ancient  learning  had  not, 
however,  depended  solely  on  the  Arabs.  At  the  be- 
ginning of  the  sixth  century,  before  the  taking  of 
Alexandria  by  the  followers  of  Mohammed,  St.  Bene- 
dict had  founded  the  monastery  of  Monte  Cassino  in 
Italy.  Here  was  begun  the  copying  of  manuscripts, 
and  the  preparation  of  compendiums  treating  of 
grammar,  dialectic,  rhetoric,  arithmetic,  astronomy, 
music,  and  geometry. '  These  were  based  on  ancient 
Roman  writings.  Works  like  Pliny's  Natural  His- 
tory, the  encyclopedia  of  the  Middle  Ages,  had  sur- 
vived all  the  wars  by  which  Rome  had  been  devas- 
tated. Learning,  which  in  Rome's  darkest  days  had 
found  refuge  in  Britain  and  Ireland,  returned  book 
in  hand.  Charlemagne  (800)  called  Alcuin  from 


THE  CONTINUITY  OF  SCIENCE       53 

York  to  instruct  princes  and  nobles  at  the  Frankish 
court.  At  this  same  palace  school  half  a  century 
later  the  Irishman  Scotus  Erigena  exhibited  his  learn- 
ing, wit,  and  logical  acumen.  In  the  tenth  century 
Gerbert  (Pope  Sylvester  II)  learned  mathematics 
at  Arab  schools  in  Spain.  The  translation  of  Arab 
works  on  science  into  the  Latin  language,  freer  in- 
tercourse of  European  peoples  with  the  East  through 
war  and  trade,  economic  prosperity,  the  liberation 
of  serfs  and  the  development  of  a  well-to-do  middle  V 
class,  the  voyages  of  Marco  Polo  to  the  Orient,  the 
founding  of  universities,  the  encouragement  of  learn- 
ing by  the  Emperor  Frederick  II,  the  study  of  logic 
by  the  schoolmen,  were  all  indicative  of  a  new  era  in 
the  history  of  scientific  thought. 

The  learned  Dominican  Albertus  Magnus  (1193- 
1280)  was  a  careful  student  of  Aristotle  as  well  as 
of  his  Arabian  commentators.  In  his  many  books  on 
natural  history  he  of  course  pays  great  deference  to 
the  Philosopher,  but  he  is  not  devoid  of  original  ob- 
servation. As  the  official  visitor  of  his  order  he  had 
traveled  through  the  greater  part  of  Germany  on 
foot,  and  with  a  keen  eye  for  natural  phenomena  was 
able  to  enrich  botany  and  zoology  by  much  accurate 
information.  His  intimacy  with  the  details  of  natu- 
ral history  made  him  suspected  by  the  ignorant  of 
the  practice  of  magical  arts. 

His  pupil  and  disciple  Thomas  Aquinas  (1227- 
1274)  was  the  philosopher  and  recognized  champion 
of  the  Christian  Church.  In  1879  Pope  Leo  XIII, 
while  proclaiming  that  every  wise  saying,  every  use- 
ful discovery,  by  whomsoever  it  may  be  wrought, 
should  be  welcomed  with  a  willing  and  grateful 


54  THE  HISTORY  OF  SCIENCE 

mind,  exhorted  the  leaders  of  the  Roman  Catholic 
Church  to  restore  the  golden  wisdom  of  St.  Thomas 
and  to  propagate  it  as  widely  as  possible  for  the  good 
of  society  and  the  advancement  of  all  the  sciences. 
Certainly  the  genius  of  St.  Thomas  Aquinas  seems 
comprehensive  enough  to  embrace  all  science  as  well 
as  all  philosophy  from  the  Christian  point  of  view. 
According  to  him  there  are  two  sources  of  knowl- 
edge, reason  and  revelation.  These  are  not  irrecon- 
cilably opposed.  The  Greek  philosophers  speak  with 
the  voice  of  reason.  It  is  the  duty  of  theology  to 
bring  all  knowledge  into  harmony  with  the  truths  of 
revelation  imparted  by  God  for  the  salvation  of  the 
human  race.  Averroes  is  in  error  when  he  argues 
the  impossibility  of  something  being  created  from 
nothing,  and  again  when  he  implies  that  the  individ- 
ual intellect  becomes  merged  in  a  transcendental  in- 
tellect ;  for  such  teaching  would  be  the  contrary  of 
what  has  been  revealed  in  reference  to  the  creation 
of  the  world  and  the  immortality  of  the  individual 
soul.  In  the  accompanying  illustration  we  see  St. 
Thomas  inspired  by  Christ  in  glory,  guided  by  Moses, 
St.  Peter,  and  the  Evangelists,  and  instructed  by 
Aristotle  and  Plato.  He  has  overcome  the  heathen 
philosopher  Averroes,  who  lies  below  discomfited. 

The  English  Franciscan  Roger  Bacon  (1214- 
1294)  deserves  to  be  mentioned  with  the  two  great 
Dominicans.  He  was  acquainted  with  the  works  of 
the  Greek  and  Arabian  scientists.  He  transmitted 
in  a  treatise  that  fell  under  the  eye  of  Columbus  the 
view  of  Aristotle  in  reference  to  the  proximity  of  an- 
other continent  on  the  other  side  of  the  Atlantic  ;  he 
anticipated  the  principle  on  which  the  telescope  was 


' 

Jt3?  -  j>  -1  « 

"(-.'>!%     /       , 


»  >  ft  *  I 

.      ".!»•*&*» 
•       • 

|    «  »   *||^ 

*   )>    ft 

»     '>r-     r    .     s 
t     ' 

. 


4  *  «  rt   ,->*«•*    • 


ST.  THOMAS  AQUINAS  OVERCOMING  AVERROftS 


THE  CONTINUITY  OF  SCIENCE       55 

afterwards  constructed ;  he  advocated  basing  natural 
science  on  experience  and  careful  observation  rather 
than  on  a  process  of  reasoning.  Roger  Bacon's  writ- 
ings are  characterized  by  a  philosophical  breadth  of 
view.  To  his  mind  the  earth  is  only  an  insignificant 
dot  in  the  center  of  the  vast  heavens. 

In  the  centuries  that  followed  the  death  of  Bacon 
the  relation  of  this  planet  to  the  heavenly  bodies  was 
made  an  object  of  study  by  a  succession  of  scientists 
who  like  him  were  versed  in  the  achievements  of  pre- 
ceding ages.  Peurbach  (1423-1461),  author  of  New 
Tfieorics  of  the  Planets,  developed  the  trigonometry 
of  the  Arabians,  but  died  before  fulfilling  his  plan 
to  give  Europe  an  epitome  of  the  astronomy  of 
Ptolemy.  His  pupil,  Regiomontanus,  however,  more 
than  made  good  the  intentions  of  his  master.  The 
work  of  Peurbach  had  as  commentator  the  first 
teacher  in  astronomy  of  Copernicus  (1473-1543). 
Later  Copernicus  spent  nine  years  in  Italy,  study- 
ing at  the  universities  and  acquainting  himself  with 
Ptolemaic  and  other  ancient  views  concerning  the 
motions  of  the  planets.  He  came  to  see  that  the  ap- 
parent revolution  of  the  heavenly  bodies  about  the 
earth  from  east  to  west  is  really  owing  to  the  revolu- 
tion of  the  earth  on  its  axis  from  west  to  east.  This 
view  was  so  contrary  to  prevailing  beliefs  that  Co- 
pernicus refused  to  publish  his  theory  for  thirty-six 
years.  A  copy  of  his  book,  teaching  that  our  earth  is 
not  the  center  of  the  universe,  was  brought  to  him  on 
his  deathbed,  but  he  never  opened  it. 

Momentous  as  was  this  discovery,  setting  aside  the 
geocentric  system  which  had  held  captive  the  best 
minds  for  fourteen  slow  centuries  and  substituting  the 


56          THE  HISTORY  OF  SCIENCE 

heliocentric,  it  was  but  a  link  in  the  chain  of  suc- 
cesses in  astronomy  to  which  Tycho  Brahe,  Kepler, 
Galileo,  Newton,  and  their  followers  contributed. 

REFERENCES 

The  Catholic  Encyclopedia. 

J.  L.  E.  Dreyer,  History  of  the  Planetary  Systems. 
Encyclopaedia  Britannica.  Arabian  Philosophy;  Roger  Bacon. 
W.  J.  Townsend,  The  Great  Schoolmen  of  the  Middle  Ages. 
R.  B.  Vaughan,  St.  Thomas  of  Aquin  ;  his  Life  and  Labours. 
Andrew  D.  White,  A  History  of  the  Warfare  of  Science  with  Theol- 
ogy in  Christendom. 


CHAPTER  V 

THE   CLASSIFICATION   OF   THE  SCIENCES 

FRANCIS   BACON 

THE  preceding  chapter  has  shown  that  there  is  a 
continuity  in  the  development  of  single  sciences.  The 
astronomy,  or  the  chemistry,  or  the  mathematics, 
of  one  period  depends  so  directly  on  the  respective 
science  of  the  foregoing  period,  that  one  feels  justi- 
fied in  using  the  term  "growth,"  or  "evolution,"  to 
describe  their  progress.  Now  a  vital  relationship  can 
be  observed  not  only  among  different  stages  of  the 
same  science,  but  also  among  the  different  sciences. 
Physics,  astronomy,  and  chemistry  have  much  in 
common ;  geometry,  trigonometry,  arithmetic,  and 
algebra  are  called  "  branches  "  of  mathematics  ;  zo- 
ology and  botany  are  biological  sciences,  as  having 
to  do  with  living  species.  In  the  century  following 
the  death  of  Copernicus,  two  great  scientists,  Bacon 
and  Descartes,  compared  all  knowledge  to  a  tree, 
of  which  the  separate  sciences  are  branches.  They 
thought  of  all  knowledge  as  a  living  organism  with 
an  interconnection  or  continuity  of  parts,  and  a  ca- 
pability of  growth. 

By  the  beginning  of  the  seventeenth  century  the 
sciences  were  so  considerable  that  in  the  interest  of 
further  progress  a  comprehensive  view  of  the  tree 
of  knowledge,  a  survey  of  the  field  of  learning,  was 
needed.  The  task  of  making  this  survey  was  under- 
taken by  Francis  Bacon,  Lord  Verulain  (1561-1626). 


58  THE  HISTORY  OF  SCIENCE 

His  classification  of  human  knowledge  was  cele- 
brated, and  very  influential  in  the  progress  of  sci- 
ence. He  kept  one  clear  purpose  in  view,  namely, 
the  control  of  nature  by  man.  He  wished  to  take 
stock  of  what  had  already  been  accomplished,  to  sup- 
ply deficiencies,  and  to  enlarge  the  bounds  of  human 
empire.  He  was  acutely  conscious  that  this  was  an 
enterprise  too  great  for  any  one  man,  and  he  used  his 
utmost  endeavors  to  induce  James  I  to  become  the 
patron  of  the  plan.  His  project  admits  of  very  simple 
statement  now ;  he  wished  to  edit  an  encyclopedia, 
but  feared  that  it  might  prove  impossible  without  co- 
operation and  without  state  support.  He  felt  capable 
of  furnishing  the  plans  for  the  building,  but  thought 
it  a  hardship  that  he  was  compelled  to  serve  both  as 
architect  and  laborer.  The  worthiness  of  these  plans 
was  attested  in  the  middle  of  the  eighteenth  century, 
when  the  great  French  Encyclopaedia  was  projected  by 
Diderot  and  D'Alembert.  The  former,  its  chief  edi- 
tor and  contributor,  wrote  in  the  Prospectus  :  "  If 
we  come  out  successful  from  this  vast  undertaking, 
we  shall  owe  it  mainly  to  Chancellor  Bacon,  who 
sketched  the  plan  of  a  universal  dictionary  of  sciences 
and  arts  at  a  time  when  there  were  not,  so  to  speak, 
either  arts  or  sciences.  This  extraordinary  genius, 
when  it  was  impossible  to  write  a  history  of  what  men 
knew,  wrote  one  of  what  they  had  to  learn." 

Bacon,  as  we  shall  amply  see,  was  a  firm  believer 
in  the  study  of  the  arts  and  occupations,  and  at  the 
same  time  retained  his  devotion  to  principles  and  ab- 
stract thought.  He  knew  that  philosophy  could  aid 
the  arts  that  supply  daily  needs ;  also  that  the  arts 
and  occupations  enriched  the  field  of  philosophy, 


CLASSIFICATION  OF  THE  SCIENCES    59 

and  that  the  basis  of  our  generalizations  must  be 
the  universe  of  things  knowable.  "  For,"  he  writes, 
"  if  men  judge  that  learning  should  be  referred  to 
use  and  action,  they  judge  well ;  but  it  is  easy  in  this 
to  fall  into  the  error  pointed  out  in  the  ancient  fable  ; 
in  which  the  other  parts  of  the  body  found  fault  with 
the  stomach,  because  it  neither  performed  the  office 
of  motion  as  the  limbs  do,  nor  of  sense,  as  the  head 
does ;  but  yet  notwithstanding  it  is  the  stomach  which 
digests  and  distributes  the  aliment  to  all  the  rest.  So 
that  if  any  man  think  that  philosophy  and  universal- 
ity are  idle  and  unprofitable  studies,  he  does  not  con- 
sider that  all  arts  and  professions  are  from  thence 
supplied  with  sap  and  strength."  For  Bacon,  as  for 
Descartes,  natural  philosophy  was  the  trunk  of  the 
tree  of  knowledge. 

On  the  other  hand,  he  looked  to  the  arts,  crafts,  and 
occupations  as  a  source  of  scientific  principles.  In  his 
survey  of  learning  he  found  some  records  of  agri- 
culture and  likewise  of  many  mechanical  arts.  Some 
think  them  a  kind  of  dishonor.  "  But  if  my  judgment 
be  of  any  weight,  the  use  of  History  Mechanical  is, 
of  all  others,  the  most  radical  and  fundamental 
towards  natural  philosophy."  When  the  different 
arts  are  known,  the  senses  will  furnish  sufficient 
concrete  material  for  the  information  of  the  under- 
standing. The  record  of  the  arts  is  of  most  use  be- 
cause it  exhibits  things  in  motion,  and  leads  more 
directly  to  practice.  "  Upon  this  history,  therefore, 
mechanical  and  illiberal  as  it  may  seem  (all  fineness 
and  daintiness  set  aside),  the  greatest  diligence  must 
be  bestowed."  "  Again,  among  the  particular  arts 
those  are  to  be  preferred  which  exhibit,  alter,  and  pre- 


Philosophia  prima,  or  sapience 


Civil  Philosophy 

(Standards  of 

right  in :) 


Philosophy 
of  Humanity 
(Anthropol- 
ogy) 


Body 


Soul 


Intercourse 

Business 

Government 


Medicine,  Athletics,  etc. 


Logic 
Ethics 


Speculative 


Operative 


Physics 

(Material  and  Second- 
ary Causes) 

Metaphysics 
(Form  and  Final 
Causes) 


Concrete 
Abstract 
Concrete 
Abstract 


Mechanics 
Purified  Magic 


Natural  Theology,  Nature  of  Angels  and  Spirits 


Revelation 


•5          Narrative,  or  Heroical 
Dramatic 
Parabolic  (Fables) 


o  g 

li 


Political 
(Civil  History  proper) 


Memorials 
Antiquities 
Perfect  History 


Literary 


Learning 

Arts 


Ecclesiastical 


Bonds 
(Control  by  Man) 


Errors 
(Anomics) 


Freedom 
(Nomic  Law) 


Arts 


Mechanical 
Experimental 


Pretergenerations 
(Monsters) 


Generations 


Astronomical  Physics 
Physical  Geography 
Physics  of  Matter 
Organic  Species 


Knowledge  Classified  (Hugo  of  St.  Victor,  d.  1141). 


Theoretical 


Theology 

Natural  Philosophy 
(Physic) 


Mathematics 


Arithmetic 

Music  (study  of  harmony) 

Geometry 

Astronomy 


Practical 
(Moral) 


Ethics,  or  individual  morality 
Economics,  or  family  morality 
Politics,  or  civics 


Mechanical 


Weaving,  spinning,  sewing;  work  in  wool,  flax,  etc. 

Equipment  — arms,  ships;  work  in  stone,  wood,  metal 

Navigation 

Agriculture 

Hunting,  fishing,  foods 

Medicine 

Theatricals  — drama,  music,  athletics,  etc. 


Logical 


Oratory 
Grammar 
Dialectic 
Rhetoric 


62  THE  HISTORY  OF  SCIENCE 

pare  natural  bodies  and  materials  of  things  as  agri- 
culture, cooking,  chemistry,  dyeing ;  the  manufacture 
of  glass,  enamel,  sugar,  gunpowder,  artificial  fires, 
paper  and  the  like."  Weaving,  carpentry,  architec- 
ture, manufacture  of  mills,  clocks,  etc.  follow.  The 
purpose  is  not  solely  to  bring  the  arts  to  perfection, 
but  all  mechanical  experiments  should  be  as  streams 
flowing  from  all  sides  into  the  sea  of  philosophy. 

Shortly  after  James  I  came  to  the  throne  in  1603, 
Bacon  published  his  Advancement  of  Learning.  He 
continued  in  other  writings,  however,  to  develop  the 
organization  of  knowledge,  and  in  1623  summed  up 
his  plan  in  the  De  Augmentis  Scientiarum. 

A  recent  writer  (Pearson,  1900)  has  attempted 
to  summarize  Bacon's  classification  of  the  different 
branches  of  learning.  When  one  compares  this  sum- 
mary with  an  outline  of  the  classification  of  knowl- 
edge made  by  the  French  monk,  Hugo  of  St.  Victor, 
who  stands  midway  between  Isidore  of  Seville  (570- 
636)  and  Bacon,  some  points  of  resemblance  are  of 
course  obvious.  Moreover,  Hugo,  like  Bacon,  insisted 
on  the  importance  of  not  being  narrowly  utilitarian. 
Men,  he  says,  are  often  accustomed  to  value  knowl- 
edge not  on  its  own  account  but  for  what  it  yields. 
Thus  it  is  with  the  arts  of  husbandry,  weaving,  paint- 
ing, and  the  like,  where  skill  is  considered  absolutely 
vain,  unless  it  results  in  some  useful  product.  If, 
however,  we  judged  after  this  fashion  of  God's  wis- 
dom, then,  no  doubt,  the  creation  would  be  preferred 
to  the  Creator.  But  wisdom  is  life,  and  the  love  of 
wisdom  is  the  joy  of  life  (felicitasvitce). 

Nevertheless,  when  we  compare  these  classifications 
diligently,  we  find  very  marked  differences  between 


CLASSIFICATION  OF  THE  SCIENCES    63 

Bacon's  views  and  the  medieval.  The  weakest  part 
of  Hugo's  classification  is  that  which  deals  with 
natural  philosophy.  Physica,  he  says,  undertakes  the 
investigation  of  the  causes  of  things  in  their  effects, 
and  of  effects  in  their  causes.  It  deals  with  the  ex- 
planation of  earthquakes,  tides,  the  virtues  of  plants, 
the  fierce  instincts  of  wild  animals,  every  species  of 
stone,  shrub,  and  reptile.  When  we  turn  to  his  spe- 
cial work,  however,  on  this  branch  of  knowledge, 
Concerning  Beasts  and  Other  Things,  we  find  no 
attempt  to  subdivide  the  field  of  physica,  but  a  se- 
ries of  details  in  botany,  geology,  zoology,  and  human 
anatomy,  mostly  arranged  in  dictionary  form. 

When  we  refer  to  Bacon's  classification  we  find 
that  Physics  corresponds  to  Hugo's  Physica.  It 
studies  natural  phenomena  in  relation  to  their  ma- 
terial causes.  For  this  study,  Natural  History,  ac- 
cording to  Bacon,  supplies  the  facts.  Let  us  glance, 
then,  at  his  work  on  natural  history,  and  see  how 
far  he  had  advanced  from  the  medieval  toward  the 
modern  conception  of  the  sciences. 

For  purposes  of  scientific  study  he  divided  the 
phenomena  of  the  universe  into  (1)  Celestial  phe- 
nomena ;  (2)  Atmosphere ;  (3)  Globe ;  (4)  Substance 
of  earth,  air,  fire,  water;  (5)  Genera,  species,  etc. 
Great  scope  is  given  to  the  natural  history  of  man. 
The  arts  are  classified  as  nature  modified  by  man. 
History  means,  of  course,  descriptive  science. 


64          THE  HISTORY  OF  SCIENCE 

Bacon's  Catalogue  of  Particular  Histories  by  Titles 
(1620) 

1.  History  of  the  Heavenly  Bodies;  or  Astronomical 
History. 

2.  History  of  the  Configuration  of  the  Heavens  and  the 
parts  thereof  towards  the  Earth  and  the  parts  thereof; 
or  Cosmographical  History. 

3.  History  of  Comets. 

4.  History  of  Fiery  Meteors. 

5.  History  of  Lightnings,  Thunderbolts,  Thunders,  and 
Coruscations. 

6.  History  of  Winds  and  Sudden  Blasts  and  Undulations 
of  the  Air. 

7.  History  of  Rainbows. 

8.  History  of  Clouds,  as  they  are  seen  above. 

9.  History  of  the  Blue  Expanse,  of  Twilight,  of  Mock- 
Suns,  Mock-Moons,  Haloes,  various  colours  of  the 
Sun;  and  of  every  variety  in  the  aspect  of  the  heav- 
ens caused  by  the  medium. 

10.  History  of  Showers,  Ordinary,  Stormy,  and  Prodi- 
gious; also  of  Waterspouts  (as  they  are  called);  and 
the  like. 

11.  History  of  Hail,  Snow,  Frost,  Hoar-frost,  Fog,  Dew, 
and  the  like. 

12.  History  of  all  other  things  that  fall  or  descend  from 
above,  and  that  are  generated  in  the  upper  region. 

13.  History  of  Sounds  in  the  upper  region  (if  there  be 
any)",  besides  Thunder. 

14.  History  of  Air  as  a  whole,  or  in  the  Configuration  of 
the  World. 

15.  History  of  the  Seasons  or  Temperatures  of  the  Year, 
as  well  according  to  the  variations  of  Regions  as  ac- 
cording to  accidents  of  Times  and  Periods  of  Years; 
of  Floods,  Heats,  Droughts,  and  the  like. 

16.  History  of  Earth  and  Sea;  of  the  Shape  and  Compass 
of  them,  and  their  Configurations  compared  with  each 
other;  and  of  their  broadening  or  narrowing;  of  Islands 
in  the  Sea;  of  Gulfs  of  the  Sea,  and  Salt  Lakes  within 
the  Land;  Isthmuses  and  Promontories. 


CLASSIFICATION  OF  THE  SCIENCES    65 

17.  History  of  the  Motions  (if  any  be)  of  the  Globe  of 
Earth  and  Sea;  and  of  the  Experiments  from  which 
such  motions  may  be  collected. 

18.  History  of  the  greater  motions  and  Perturbations  in 
Earth  and  Sea;  Earthquakes,  Tremblings  and  Yawn- 
ings  of  the  Earth,  Islands  newly  appearing;  Float- 
ing Islands;  Breakings  off  of  Land  by  entrance  of 
the  Sea,  Encroachments  and  Inundations  and  con- 
trariwise Recessions  of  the  Sea;  Eruptions  of  Fire 
from  the  Earth;  Sudden  Eruptions  of  Waters  from 
the  Earth;  and  the  like. 

19.  Natural  History  of  Geography;  of  Mountains,  Vallies, 
Woods,  Plains,  Sands,  Marshes,  Lakes,  Rivers,  Tor- 
rents, Springs,  and  every  variety  of  their  course,  and 
the  like;  leaving  apart  Nations,  Provinces,  Cities, 
and  such  like  matters  pertaining  to  Civil  life. 

20.  History  of  Ebbs  and  Flows  of  the  Sea;  Currents,  Un- 
dulations, and  other  Motions  of  the  Sea. 

21.  History  of  other  Accidents  of  the  Sea;  its  Saltness,  its 
various  Colours,  its  Depth;  also  of  Rocks,  Mountains, 
and  Vallies  under  the  Sea,  and  the  like. 

Next  come  Histories  of  the  Greater  Masses 

22.  History  of  Flame  and'of  things  Ignited. 

23.  History  of  Air,  in  Substance,  not  in  the  Configuration 
of  the  World. 

24.  History  of  Water,  in  Substance,  not  in  the  Configu- 
ration of  the  World. 

25.  History  of  the  Earth  and  the  diversity  thereof,  in 
Substance,  not  in  the  Configuration  of  the  World. 

Next  come  Histories  of  Species 

26.  History  of  perfect  Metals,  Gold,  Silver;  and  of  the 
Mines,  Veins,  Marcasites  of  the  same;  also  of  the 
Working  in  the  Mines. 

27.  History  of  Quicksilver. 

28.  History  of  Fossils;  as  Vitriol,  Sulphur,  etc. 

29.  History  of  Gems;  as  the  Diamond,  the  Ruby,  etc. 


66  THE  HISTORY  OF  SCIENCE 

SO.  History  of  Stones;  as  Marble,  Touchstone,  Flint,  etc. 
81.  History  of  the  Magnet. 

32.  History  of  Miscellaneous  Bodies,  which  are  neither 
entirely  Fossil  nor  Vegetable;  as  Salts,  Amber,  Am- 
bergris, etc. 

33.  Chemical  History  of  Metals  and  Minerals. 

34.  History  of  Plants,  Trees,  Shrubs,  Herbs;  and  of  their 
parts,  Roots,  Stalks,  Wood,  Leaves,  Flowers,  Fruits, 
Seeds,  Gums,  etc. 

35.  Chemical  History  of  Vegetables. 

36.  History  of  Fishes,  and  the  Parts  and  Generation  of 
them. 

37.  History  of  Birds,  and  the  Parts  and  Generation  of 
them. 

38.  History  of  Quadrupeds,  and  the  Parts  and  Generation 
of  them. 

39.  History  of  Serpents,  Worms,  Flies,  and  other  insects; 
and  of  the  Parts  and  Generation  of  them. 

40.  Chemical  History  of  the  things  which  are  taken  by 
Animals. 

Next  come  Histories  of  Man 

41.  History  of  the  Figure  and  External  Limbs  of  man,  his 
Stature,  Frame,  Countenance,  and  Features;  and  of 
the  variety  of  the  same  according  to  Races  and 
Climates,  or  other  smaller  differences. 

42.  Physiognomical  History  of  the  same. 

43.  Anatomical  History,  or  of  the  Internal  Members  of 
Man;  and  of  the  variety  of  them,  as  it  is  found  in  the 
Natural  Frame  and  Structure,  and  not  merely  as 
regards  Diseases  and  Accidents  out  of  the  course  of 
Nature. 

44.  History  of  the  parts  of  Uniform  Structure  in  Man; 
as  Flesh,  Bones,  Membranes,  etc. 

45.  History  of  Humours  in  Man;  Blood,  Bile,  Seed,  etc. 

46.  History  of  Excrements;  Spittle,  Urine,  Sweats,  Stools, 
Hair  of  the  Head,  Hairs  of  the  Body,  Whitlows,  Nails, 
and  the  like. 

47.  History  of  Faculties;  Attraction,  Digestion,  Reten- 


CLASSIFICATION  OF  THE  SCIENCES    67 

tion,  Expulsion,  Sanguification,  Assimilation  of  Ali- 
ment into  the  members,  conversion  of  Blood  and 
Flower  of  Blood  into  Spirit,  etc. 

48.  History  of  Natural  and  Involuntary  Motions;  as  Mo- 
tion  of   the   Heart,   the   Pulses,   Sneezing,   Lungs, 
Erection,  etc. 

49.  History  of  Motions  partly  Natural  and  Partly  Violent; 
as  of  Respiration,  Cough,  Urine,  Stool,  etc. 

50.  History  of  Voluntary  Motions;  as  of  the  Instruments 
of  Articulation   of  Words;   Motions   of  the  Eyes. 
Tongue,  Jaws,  Hands,  Fingers;  of  Swallowing,  etc. 

51.  History  of  Sleep  and  Dreams. 

52.  History  of  different  habits  of  Body  —  Fat,  Lean; 
of  the  Complexions  (as  they  call  them),  etc. 

53.  History  of  the  Generation  of  Man. 

54.  History  of  Conception,  Vivification,  Gestation  in  the 
Womb,  Birth,  etc. 

55.  History  of  the  Food  of  Man;  and  of  all  things  Eatable 
and  Drinkable;  and  of  all  Diet;  and  of  the  variety 
of  the  same  according  to  nations  and  smaller  differ- 
ences. 

56.  History  of  the  Growth  and  Increase  of  the  Body,  in 
the  whole  and  in  its  parts. 

57.  History  of  the  Course  of  Age;  Infancy,  Boyhood, 
Youth,  Old  Age;  of  Length  and  Shortness  of  Life,  and 
the  like,  according  to  nations  and  lesser  differences. 

58.  History  of  Life  and  Death. 

59.  History  Medicinal  of  Diseases,  and  of  the  Symptoms 
and  Signs  of  them. 

60.  History  Medicinal  of  the  Treatment  and  Remedies 
and  Cures  of  Diseases. 

61.  History  Medicinal  of  those  things  which  preserve  the 
Body  and  the  Health. 

62.  History  Medicinal  of  those  things  which  relate  to  the 
Form  and  Comeliness  of  the  Body. 

63.  History  Medicinal  of  those  things  which  alter  the 
Body,  and  pertain  to  Alterative  Regimen. 

64.  History  of  Drugs. 


68          THE  HISTORY  OF  SCIENCE 

65.  History  of  Surgery. 

66.  Chemical  History  of  Medicines. 

67.  History  of  Vision,  and  of  things  Visible. 

68.  History  of  Painting,  Sculpture,  Modelling,  etc. 

69.  History  of  Hearing  and  Sound. 

70.  History  of  Music. 

71.  History  of  Smell  and  Smells. 

72.  History  of  Taste  and  Tastes. 

73.  History  of  Touch,  and  the  objects  of  Touch. 

74.  History  of  Venus,  as  a  species  of  Touch. 

75.  History  of  Bodily  Pains,  as  species  of  Touch. 

76.  History  of  Pleasure  and  Pain  in  general. 

77.  History  of  the  Affections;  as  Anger,  Love,  Shame, 
etc. 

78.  History    of    the    Intellectual    Faculties;    Reflexion, 
Imagination,  Discourse,  Memory,  etc. 

79.  History  of  Natural  Divinations. 

80.  History  of  Diagnostics,  or  Secret  Natural  Judgements. 


81.  History  of  Cookery,  and  of  the  arts  thereto  belonging, 
as  of  the  Butcher,  Poulterer,  etc. 

82.  History  of  Baking,  and  the  Making  of  Bread,  and  the 
arts  thereto  belonging,  as  of  the  Miller,  etc. 

83.  History  of  Wine. 

84.  History  of  the  Cellar  and  of  different  kinds  of  Drink. 

85.  History  of  Sweetmeats  and  Confections. 

86.  History  of  Honey. 

87.  History  of  Sugar. 

88.  History  of  the  Dairy. 

89.  History  of  Baths  and  Ointments. 

90.  Miscellaneous  History  concerning  the  care  of  the 
body  —  as  of  Barbers,  Perfumers,  etc. 

91.  History  of  the  working  of  Gold,  and  the  arts  thereto 
belonging. 

92.  History  of  the  manufactures  of  Wool,  and  the  arts 
thereto  belonging. 

93.  History  of  the  manufactures  of  Silk,  and   the  arts 
thereto  belonging. 

94.  History  of  the  manufactures  of  Flax,  Hemp,  Cotton, 


CLASSIFICATION  OF  THE  SCIENCES    69 

Hair,   and    other  kinds   of   Thread,  and    the  arts 
thereto  belonging. 

95.  History  of  manufactures  of  Feathers. 

96.  History  of  Weaving,  and  the  arts  thereto  belonging. 

97.  History  of  Dyeing. 

98.  History  of  Leather-making,  Tanning,  and  the  arts 
thereto  belonging. 

99.  History  of  Ticking  and  Feathers. 

100.  History  of  working  in  Iron. 

101.  History  of  Stone-cutting. 

102.  History  of  the  making  of  Bricks  and  Tiles. 

103.  History  of  Pottery. 

104.  History  of  Cements,  etc. 

105.  History  of  working  in  Wood. 

106.  History  of  working  in  Lead. 

107.  History  of  Glass  and  all  vitreous  substances,  and  of 
Glass-making. 

108.  History  of  Architecture  generally. 

109.  History  of  Waggons,  Chariots,  Litters,  etc. 

110.  History  of  Printing,  of  Books,  of  Writing,  of  Sealing; 
of  Ink,  Pen,  Paper,  Parchment,  etc. 

111.  History  of  Wax. 

112.  History  of  Basket-making. 

113.  History  of  Mat-making,   and    of  manufactures  of 
Straw,  Rushes,  and  the  like. 

114.  History  of  Washing,  Scouring,  etc. 

115.  History  of  Agriculture,  Pasturage,  Culture  of  Woods, 
etc. 

116.  History  of  Gardening. 

117.  History  of  Fishing. 

118.  History  of  Hunting  and  Fowling. 

119.  History  of  the  Art  of  War,  and  of  the  arts  thereto 
belonging,  as  Armoury,  Bow-making,  Arrow-making, 
Musketry,  Ordnance,  Cross-bows,  Machines,  etc. 

120.  History  of  the  Art  of  Navigation,  and  of  the  crafts 
and  arts  thereto  belonging. 

121.  History  of  Athletics  and  Human  Exercises  of  all  kinds. 

122.  History  of  Horsemanship. 

123.  History  of  Games  of  all  kinds. 

124.  History  of  Jugglers  and  Mountebanks. 


70  THE  HISTORY  OF  SCIENCE 

125.  Miscellaneous  History  of  various  Artificial  Materials, 
—  Enamel,  Porcelain,  various  cements,  etc. 

126.  History  of  Salts. 

127.  Miscellaneous  History  of  various  Machines  and  Mo- 
tions. 

128.  Miscellaneous    History    of    Common    Experiments 
which  have  not  grown  into  an  Art. 

Histories  musi  also  be  written  of  Pure  Mathematics ;  though 
they  are  rather  observations  than  experiments 

129.  History  of  the  Natures  and  Powers  of  Numbers. 

130.  History  of  the  Natures  and  Powers  of  Figures. 

The  fragment  containing  this  catalogue  (Parasceve 
—  Day  of  Preparation)  was  added  to  Bacon's  work 
on  method,  The  New  Logic  (Novum  Organum), 
1620.  Besides  completing  his  survey  and  classifica- 
tion of  the  sciences  (De  Augmentis  Scientiarum), 
1623,  he  published  a  few  separate  writings  on  topics 
in  the  catalogue  —  Winds,  Life  and  Death,  Tides, 
etc.  In  1627,  a  year  after  his  death,  appeared  his 
much  misunderstood  work,  Sylva  Sylvarum.  He  had 
found  that  the  Latin  word  sylva  meant  stuff  or  raw 
material,  as  well  as  a  wood,  and  called  this  final 
work  Sylva  Sylvarum,  which  I  would  translate, 
"Jungle  of  Raw  Material."  He  himself  referred  to 
it  as  "  an  undigested  heap  of  particulars  " ;  yet  he  was 
willing  it  should  be  published  because  "he  preferred 
the  good  of  men  to  anything  that  might  have  relation 
to  himself.''  In  it,  following  his  catalogue,  he  fulfilled 
the  promise  made  in  1620,  of  putting  nature  and  the 
arts  to  question.  Some  of  the  problems  suggested  for 
investigation  are :  congealing  of  air,  turning  air  into 
water,  the  secret  nature  of  flame,  motion  of  gravity, 


CLASSIFICATION  OF  THE  SCIENCES    71 

production  of  cold,  nourishing  of  young  creatures  in 
the  egg  or  womb,  prolongation  of  life,  the  media  of 
sound,  infectious  diseases,  accelerating  and  prevent- 
ing putrefaction,  accelerating  and  staying  growth, 
producing  fruit  without  core  or  seed,  production  of 
composts  and  helps  for  ground,  flying  in  the  air. 

In  the  New  Atlantis,  a  work  of  imagination,  Bacon 
had  represented  as  already  achieved  for  mankind 
some  of  the  benefits  he  wished  for :  artificial  metals, 
various  cements,  excellent  dyes,  animals  for  vivisec- 
tion and  medical  experiment,  instruments  which  gen- 
erate heat  solely  by  motion,  artificial  precious  stones, 
conveyance  of  sound  for  great  distances  and  in  tor- 
tuous lines,  new  explosives.  "  We  imitate,"  says  the 
guide  in  the  Utopian  land,  "  also  flights  of  birds ;  we 
have  some  degree  of  flying  in  the  air ;  we  have  ships 
and  boats  for  going  under  water."  Bacon  believed  in 
honoring  the  great  discoverers  and  inventors,  and 
advocated  maintaining  a  calendar  of  inventions. 

He  was  a  fertile  and  stimulating  thinker,  and  much 
of  his  great  influence  arose  from  the  comprehensive- 
ness that  led  to  his  celebrated  classification  of  the 
sciences. 

REFERENCES 

Bacon's  Philosophical  Works,  vol.  rv,  Parasceve,  edited  by  R.  L. 

Ellis,  J.  Spedding,  and  D.  D.  Heath. 
Karl  Pearson,  Grammar  of  Science. 
J.  A.  Thomson,  Introduction  to  Science. 


CHAPTER  VI 

SCIENTIFIC    METHOD GILBERT,   GALILEO, 

HARVEY,    DESCARTES 

THE  previous  chapter  has  given  some  indication  of 
the  range  of  the  material  which  was  demanding  scien- 
tific investigation  at  the  end  of  the  sixteenth  and  the 
beginning  of  the  seventeenth  century.  The  same 
period  witnessed  a  conscious  development  of  the 
method,  or  methods,  of  investigation.  As  we  have 
seen,  Bacon  wrote  in  1620  a  considerable  work,  The, 
New  Logic,  {Novum  Organum),  so  called  to  dis- 
tinguish it  from  the  traditional  deductive  logic.  It 
aimed  to  furnish  the  organ  or  instrument,  to  indi- 
cate the  correct  mental  procedure,  to  be  employed  in 
the  discovery  of  natural  law.  Some  seventeen  years 
later,  the  illustrious  Frenchman  Rene  Descartes 
(1596-1650)  published  his  Discourse  on  the  Method 
of  rightly  conducting  the  Reason  and  seeking  Truth 
in  the  Sciences.  Both  of  these  philosophers  illustrated 
by  their  own  investigations  the  efficiency  of  the 
methods  which  they  advocated. 

Before  1620,  however,  the  experimental  method 
had  already  yielded  brilliant  results  in  the  hands  of 
other  scientists.  We  pass  over  Leonardo  da  Vinci 
and  many  others  in  Italy  and  elsewhere,  whose  names 
should  be  mentioned  if  we  were  tracing  this  method 
toitsorigin.  By  1600  William  Gilbert  (1540-1603), 
physician  to  Queen  Elizabeth,  before  whom,  as  a 
picture  in  his  birthplace  illustrates,  he  was  called  to 


SCIENTIFIC  METHOD  73 

demonstrate  his  discoveries,  had  published  his  work 
on  the  Magnet,  the  outcome  of  about  eighteen  years 
of  critical  research.  He  may  be  considered  the  founder 
of  electrical  science.  Galileo,  who  discovered  the 
fundamental  principles  of  dynamics  and  thus  laid  the 
basis  of  modern  physical  science,  although  he  did  not 
publish  his  most  important  work  till  1638,  had  even 
before  the  close  of  the  sixteenth  century  prepared 
the  way  for  the  announcement  of  his  principles  by 
years  of  strict  experiment.  By  the  year  1616,  William 
Harvey  (1578-1657),  physician  at  the  court  of  James 
I,  and,  later,  of  Charles  I,  had,  as  the  first  modern 
experimental  physiologist,  gained  important  results 
through  his  study  of  the  circulation  of  the  blood. 

It  is  not  without  significance  that  both  Gilbert  and 
Harvey  had  spent  years  in  Italy,  where,  as  we  have 
implied,  the  experimental  method  of  scientific  re- 
search was  early  developed.  Harvey  was  at  Padua 
(1598-1602)  within  the  time  of  Galileo's  popular 
professoriate,  and  may  well  have  been  inspired  by 
the  physicist  to  explain  on  dynamical  principles  the 
flow  of  blood  through  arteries  and  veins.  This  con- 
jecture is  the  more  probable,  since  Galileo,  like  Har- 
vey and  Gilbert,  had  been  trained  in  the  study  of 
medicine.  Bacon  in  turn  had  in  his  youth  learned 
something  of  the  experimental  method  on  the  Conti- 
nent of  Europe,  and,  later,  was  well  aware  of  the 
studies  of  Gilbert  and  Galileo,  as  well  as  of  Harvey, 
who  was  indeed  his  personal  physician. 

Although  these  facts  seem  to  indicate  that  method 
may  be  transmitted  in  a  nation  or  a  profession,  or 
through  personal  association,  there  still  remains  some 
doubt  as  to  whether  anything  so  intimate  as  the 


74          THE  HISTORY  OF  SCIENCE 

mental  procedure  involved  in  invention  and  in  the 
discovery  of  truth  can  be  successfully  imparted  by 
instruction.  The  individuality  of  the  man  of  genius 
engaged  in  investigation  must  remain  a  factor  diffi- 
cult to  analyze.  Bacon,  whose  purpose  was  to  hasten 
man's  empire  over  nature  through  increasing  the 
number  of  inventions  and  discoveries,  recognized 
that  the  method  he  illustrated  is  not  the  sole  method 
of  scientific  investigation.  In  fact,  he  definitely  states 
that  the  method  set  forth  in  the  Novum  Organum 
is  not  original,  or  perfect,  or  indispensable.  He  was 
aware  that  his  method  tended  to  the  ignoring  of 
genius  and  to  the  putting  of  intelligences  on  one  level. 
He  knew  that,  although  it  is  desirable  for  the  inves- 
tigator to  free  his  mind  from  prepossessions,  and  to 
avoid  premature  generalizations,  interpretation  is  the 
true  and  natural  work  of  the  mind  when  free  from 
impediments,  and  that  the  conjecture  of  the  man  of 
genius  must  at  times  anticipate  the  slow  process  of 
painful  induction.  As  we  shall  see  in  the  nineteenth 
chapter,  the  psychology  of  to-day  does  not  know 
enough  about  the  workings  of  the  mind  to  prescribe 
a  fixed  mental  attitude  for  the  investigator.  Never- 
theless, Bacon  was  not  wrong  in  pointing  out  the 
virtues  of  a  method  which  he  and  many  others  turned 
to  good  account.  Let  us  first  glance,  however,  at  the 
activities  of  those  scientists  who  preceded  Bacon  in 
the  employment  of  the  experimental  method. 

Gilbert  relied,  in  his  investigations,  on  oft-repeated 
and  verifiable  experiments,  as  can  be  seen  from  his 
work  De  Magnet^.  He  directs  the  experimenter,  for 
example,  to  take  a  piece  of  loadstone  of  convenient 
size  and  turn  it  on  a  lathe  to  the  form  of  a  ball.  It 


SCIENTIFIC  METHOD  75 

then  may  be  called  a  terrella,  or  earthkin.  Place  on  it 
a  piece  of  iron  wire.  The  ends  of  the  wire  move  round 
its  middle  point  and  suddenly  come  to  a  standstill. 
Mark  with  chalk  the  line  along  which  the  wire  lies 
still  and  sticks.  Then  move  the  wire  to  other  spots 
on  the  terrella  and  repeat  your  procedure.  The  lines 
thus  marked,  if  produced,  will  form  meridians,  all 
coming  together  at  the  poles.  Again,  place  the  mag- 
net in  a  wooden  vessel,  and  then  set  the  vessel  afloat 
in  a  tub  or  cistern  of  still  water.  The  north  pole  of  the 
stone  will  seek  approximately  the  direction  of  the 
south  pole  of  the  earth,  etc.  It  was  on  the  basis  of 
scores  of  experiments  of  this  sort,  carried  on  from 
about  1582  till  1600,  that  Gilbert  felt  justified  in 
concluding  that  the  terrestrial  globe  is  a  magnet. 
This  theory  has  since  that  time  been  abundantly 
confirmed  by  navigators.  The  full  title  of  his  book 
is  Concerning  the  Magnet  and  Magnetic  Bodies, 
and  concerning  the  Great  Magnet  the  Earth:  A 
New  Natural  History  (Physiologia)  demonstrated 
by  many  Arguments  and  Experiments.  It  does  not 
detract  from  the  credit  of  Gilbert's  result  to  state 
that  his  initial  purpose  was  not  to  discover  the  nature 
of  magnetism  or  electricity,  but  to  determine  the  true 
substance  of  the  earth,  the  innermost  constitution  of 
the  globe.  He  was  fully  conscious  of  his  own  method 
and  speaks  with  scorn  of  certain  writers  who,  having 
made  no  magnetical  experiments,  constructed  ratio- 
cinations on  the  basis  of  mere  opinions  and  old- 
worn  anishly  dreamed  the  things  that  were  not. 

Galileo  (1564-1642)  even  as  a  child  displayed 
something  of  the  inventor's  ingenuity,  and  when  he 
was  nineteen,  shortly  after  the  beginning  of  Gilbert's 


76  THE  HISTORY  OF  SCIENCE 

experiments,  his  keen  perception  for  the  phenomena  of 
motion  led  to  his  making  a  discovery  of  great  scien- 
tific moment.  He  observed  a  lamp  swinging  by  a  long 
chain  in  the  cathedral  of  his  native  city  of  Pisa,  and 
noticed  that,  no  matter  how  much  the  range  of  the 
oscillations  might  vary,  their  times  were  constant. 
He  verified  his  first  impressions  by  counting  his 
pulse,  the  only  available  timepiece.  Later  he  invented 
simple  pendulum  devices  for  timing  the  pulse  of  pa- 
tients, and  even  made  some  advances  in  applying  his 
discovery  in  the  construction  of  pendulum  clocks. 

In  1589  he  was  appointed  professor  of  mathemat- 
ics in  the  University  of  Pisa,  and  within  a  year 
or  two  established  through  experiment  the  founda- 
tions of  the  science  of  dynamics.  As  early  as  1590 
he  put  on  record,  in  a  Latin  treatise  Concerning 
Motion  (De  Motu),  his  dissent  from  the  theories  of 
Aristotle  in  reference  to  moving  bodies,  confuting 
the  Philosopher  both  by  reason  and  ocular  demon- 
stration. Aristotle  had  held  that  two  moving  bodies 
of  the  same  sort  and  in  the  same  medium  have 
velocities  in  proportion  to  their 
weights.  If  a  moving  body,  whose 
weight  is  represented  by  5,  be  car- 
ried through  the  line  c — e  which 
is  divided  in  the  point  d,  if,  also, 
the  moving  body  is  divided  accord- 
ing to  the  same  proportion  as  line 
c — e  is  in  the  point  d,  it  is  manifest 
that  in  the  time  taken  to  carry  the 
whole  body  through  c — e,  the  part 
will  be  moved  through  c — d.  Gali- 
leo said  that  it  is  as  clear  as  day- 


SCIENTIFIC  METHOD  77 

light  that  this  view  is  ridiculous,  for  who  would  be- 
lieve that  when  two  lead  spheres  are  dropped  from  a 
great  height,  the  one  being  a  hundred  times  heavier 
than  the  other,  if  the  larger  took  an  hour  to  reach 
the  earth,  the  smaller  would  take  a  hundred  hours  ? 
Or,  that  if  from  a  high  tower  two  stones,  one  twice 
the  weight  of  the  other,  should  be  pushed  out  at  the 
same  moment,  the  larger  would  strike  the  ground 
while  the  smaller  was  still  midway?  His  biography 
jtells  that  Galileo  in  the  presence  of  professors  and 
Students  dropped  bodies  of  different  weights  from 
)the  height  of  the  Leaning  Tower  of  Pisa  to  demon- 
btrate  the  truth  of  his  views.  If  allowance  be  made 
for  the  friction  of  the  air,  all  bodies  fall  from  the 
same  height  in  equal  times :  the  final  velocities  are 
proportional  to  the  times  ;  the  spaces  passed  through 
iare  proportional  to  the  squares  of  the  times.  The 
[experimental  basis  of  the  last'  two  statements  was 
furnished  by  means  of  an  inclined  plane,  down  a 
smooth  groove  in  which  a  bronze  ball  was  allowed  to 
pass,  the  time  being  ascertained  by  means  of  an 
improvised  water-clock. 

Galileo's  mature  views  on  dynamics  received  ex- 
pression in  a  work  published  in  1638,  Mathematical 
Discourses  and  Demonstrations  concerning  Two 
New  Sciences  relating  to  Mechanics  and  Local 
Movements.  It  treats  of  cohesion  and  resistance  to 
fracture  (strength  of  materials),  and  uniform,  ac- 
celerated, and  projectile  motion  (dynamics).  The  dis- 
cussion is  in  conversation  form.  The  opening  sentence 
shows  Galileo's  tendency  to  base  theory  on  the  em- 
pirical. It  might  be  freely  translated  thus :  "  Large 
scope  for  intellectual  speculation,  I  should  think, 


78  THE  HISTORY  OF  SCIENCE 

would  be  afforded,  gentlemen,  by  frequent  visits  to 
your  famous  Venetian  Dockyard  (ar senate) ,  espe- 
cially that  part  where  mechanics  are  in  demand  ; 
seeing  that  there  every  sort  of  instrument  and  ma- 
chine is  put  to  use  by  numbers  of  workmen,  among 
whom,  taught  both  by  tradition  and  their  own  ob- 
servation, there  must  be  some  very  skillful  and  also 
able  to  talk."  The  view  of  the  shipbuilders,  that  a 
large  galley  before  being  set  afloat  is  in  greater  dan- 
ger of  breaking  under  its  own  weight  than  a  small 
galley,  is  the  starting-point  of  this  most  important 
of  Galileo's  contributions  to  science. 

Vesalius  (1514-1564)  had  in  his  work  on  the 
structure  of  the  human  body  (I)e  Humani  Corporis 
Fabrica,  1543)  shaken  the  authority  of  Galen's 
anatomy ;  it  remained  for  Harvey  on  the  basis  of 
the  new  anatomy  to  improve  upon  the  Greek  physi- 
cian's experimental  physiology.  Harvey  professed  to 
learn  and  teach  anatomy,  not  from  books,  but  from 
dissections,  not  from  the  dogmas  of  the  philosophers, 
but  from  the  fabric  of  nature. 

There  have  come  down  to  us  notes  of  his  lectures 
on  anatomy  delivered  first  in  1616.  A  brief  extract 
will  show  that  even  at  that  date  he  had  already  for- 
mulated a  theory  of  the  circulation  of  the  blood :  — 

"  Wfl  By  the  structure  of  the  heart  it  appears 
that  the  blood  is  continually  transfused  through  the 
lungs  to  the  aorta  —  as  by  the  two  clacks  of  a  water- 
ram  for  raising  water. 

"  It  is  shown  by  ligature  that  there  is  continuous 
motion  of  the  blood  from  arteries  to  veins. 

1  This  is  Harvey's  monogram,  which  he  used  in  his  notes  to 
mark  any  original  observation. 


SCIENTIFIC  METHOD  79 

"  Whence  A  it  is  demonstrated  that  there  is  a  con- 
tinuous motion  of  the  blood  in  a  circle,  affected  by 
the  beat  of  the  heart." 

It  was  not  till  1628  that  Harvey  published  his 
Anatomical  Disquisition  on  the  Motion  of  the  Heart 
and  Blood  in  Animals.  It  gives  the  experimental 
basis  of  his  conclusions.  If  a  live  snake  be  laid  open, 
the  heart  will  be  seen  pulsating  and  propelling  its 
contents.  Compress  the  large  vein  entering  the  heart, 
and  the  part  intervening  between  the  point  of  constric- 
tion and  the  heart  becomes  empty  and  the  organ  pales 
and  shrinks.  Remove  the  pressure,  and  the  size  and 
color  of  the  heart  are  restored.  Now  compress  the 
artery  leading  from  the  organ,  and  the  part  between 
the  heart  and  the  point  of  pressure,  and  the  heart 
itself,  become  distended  and  take  on  a  deep  purple 
color.  The  course  of  the  blood  is  evidently  from  the 
vena  cava  through  the  heart  to  the  aorta.  Harvey  in 
his  investigations  made  use  of  many  species  of  ani- 
mals —  at  least  eighty-seven. 

It  was  believed  by  some,  before  Harvey's  demon- 
strations, that  the  arteries  were  hollow  pipes  carry- 
ing air  from  the  lungs  throughout  the  body,  although 
Galen  had  shown  by  cutting  a  dog's  trachea,  inflat- 
ing the  lungs  and  .tying  the  trachea,  that  the  lungs 
were  in  an  enclosing  sack  which  retained  the  air. 
Harvey,  following  Galen,  held  that  the  pulmonary 
artery,  carrying  blood  to  the  lungs  from  the  right 
side  of  the  heart,  and  the  pulmonary  veins,  carrying 
blood  from  the  lungs  to  the  left  side  of  the  heart,  in- 
tercommunicate in  the  hidden  porosities  of  the  lungs 
and  through  minute  inosculations. 

In  man  the  vena  cava  carries  the  blood  to  the  right 


80          THE  HISTORY  OF  SCIENCE 

side  of  the  heart,  the  pulmonary  artery  inosculates 
with  the  pulmonary  veins,  which  convey  it  to  the  left 
side  of  the  heart.  This  muscular  pump  drives  it  into 
the  aorta.  It  still  remains  to  be  shown  that  in  the 
limbs  the  blood  passes  from  the  arteries  to  the  veins. 
Bandage  the  arm  so  tightly  that  no  pulse  is  felt  at 
the  wrist.  The  hand  appears  at  first  natural,  and 
then  grows  cold.  Loose  the  bandage  sufficiently  to 
restore  the  pulse.  The  hand  and  forearm  become 
suffused  and  swollen.  In  the  first  place  the  supply 
of  blood  from  the  deep-lying  arteries  is  cut  off.  In 
the  second  case  the  blood  returning  by  the  superficial 
veins  is  dammed  back.  In  the  limbs  as  in  the  lungs 
the  blood  passes  from  artery  to  vein  by  anastomoses 
and  porosities.  All  these  arteries  have  their  source 
in  the  aorta ;  all  these  veins  pour  their  stream  ulti- 
mately into  the  vena  cava.  The  veins  have  valves, 
which  prevent  the  blood  flowing  except  toward  the 
heart.  Again,  the  veins  and  arteries  form  a  connected 
system ;  for  through  either  a  vein  or  an  artery  all 
the  blood  may  be  drained  off.  The  arguments  by 
which  Harvey  supported  his  view  were  various.  The 
opening  clause  of  his  first  chapter,  "  When  I  first 
gave  my  mind  to  vivisection  as  a  means  of  discover- 
ing the  motions  and  uses  of  the  heart,"  throws  a 
strong  light  on  his  special  method  of  experimental 
investigation. 

Bacon,  stimulated  by  what  he  called  philanthropic^, 
always  aimed,  as  we  have  seen,  to  establish  man's 
control  over  nature.  But  all  power  of  a  high  order 
depends  on  an  understanding  of  the  essential  char- 
acter, or  law,  of  heat,  light,  sound,  gravity,  and  the 
like.  Nothing  short  of  a  knowledge  of  the  underly- 


SCIENTIFIC  METHOD  81 

ing  nature  of  phenomena  can  give  science  advantage 
over  chance  in  hitting  upon  useful  discoveries  and 
inventions.  It  is,  therefore,  natural  to  find  him  ap- 
plying his  method  of  induction  —  his  special  method 
of  true  induction  —  to  the  investigation  of  heat. 

In  the  first  place,  let  there  be  mustered,  without 
premature  speculation,  all  the  instances  in  which 
heat  is  manifested  —  flame,  lightning,  sun's  rays, 
quicklime  sprinkled  with  water,  damp  hay,  animal 
heat,  hot  liquids,  bodies  subjected  to  friction.  Add 
to  these,  instances  in  which  heat  seems  to  be  absent, 
as  moon's  rays,  sun's  rays  on  mountains,  oblique  rays 
in  the  polar  circle.  Try  the  experiment  of  concen- 
trating on  a  thermoscope,  by  means  of  a  burning- 
glass,  the  moon's  rays.  Try  with  the  burning-glass 
to  concentrate  heat  from  hot  iron,  from  common 
flame,  from  boiling  water.  Try  a  concave  glass  with 
the  sun's  rays  to  see  whether  a  diminution  of  heat 
results.  Then  make  record  of  other  instances,  in 
which  heat  is  found  in  varying  degrees.  For  exam- 
ple, an  anvil  grows  hot  under  the  hammer.  A  thin 
plate  of  metal  under  continuous  blows  might  grow 
red  like  ignited  iron.  Let  this  be  tried  as  an  experi- 
ment. 

After  the  presentation  of  these  instances  induction 
itself  must  be  set  to  work  to  find  out  what  factor  is 
ever  present  in  the  positive  instances,  what  factor 
is  ever  wanting  in  the  negative  instances,  what  fac- 
tor always  varies  in  the  instances  which  show  varia- 
tion. According  to  Bacon  it  is  in  the  process  of 
exclusion  that  the  foundations  of  true  induction  are 
laid.  We  can  be  certain,  for  example,  that  the 
essential  nature  of  heat  does  not  consist  in  light  and 


82  THE  HISTORY  OF  SCIENCE 

brightness,  since  it  is  present  in  boiling  water  and 
absent  in  the  moon's  rays. 

The  induction,  however,  is  not  complete  till  some- 
thing positive  is  established.  At  this  point  in  the 
investigation  it  is  permissible  to  venture  an  hypoth- 
esis in  reference  to  the  essential  character  of  heat. 
From  a  survey  of  the  instances,  all  and  each,  it  ap- 
pears that  the  nature  of  which  heat  is  a  particular 
case  is  motion.  This  is  suggested  by  flame,  sim- 
mering liquids,  the  excitement  of  heat  by  motion, 
the  extinction  of  fire  by  compression,  etc.  Motion  is 
the  genus  of  which  heat  is  the  species.  Heat  itself, 
its  essence,  is  motion  and  nothing  else. 

It  remains  to  establish  its  specific  differences. 
This  accomplished,  we  arrive  at  the  definition  :  Heat 
is  a  motion,  expansive,  restrained,  and  acting  in  its 
strife  upon  the  smaller  particles  of  bodies.  Bacon, 
glancing  toward  the  application  of  this  discovery, 
adds :  "  If  in  any  natural  body  you  can  excite  a 
dilating  or  expanding  motion,  and  can  so  repress 
this  motion  and  turn  it  back  upon  itself,  that  the 
dilation  shall  not  proceed  equally,  but  have  its  way 
in  one  part  and  be  counteracted  in  another,  you  will 
undoubtedly  generate  heat."  The  reader  will  recall 
that  Bacon  looked  for  the  invention  of  instruments 
that  would  generate  heat  solely  by  motion. 

Descartes  was  a  philosopher  and  mathematician. 
In  his  Discourse  on  Method  and  his  Joules  for  the 
Direction  of  the  Mind  (1628)  he  laid  emphasis  on 
deduction  rather  than  on  induction.  In  the  subor- 
dination of  particulars  to  general  principles  he  ex- 
perienced a  satisfaction  akin  to  the  sense  of  beauty 
or  the  joy  of  artistic  production.  He  speaks  enthusi- 


SCIENTIFIC  METHOD  83 

astically  of  that  pleasure  which  one  feels  in  truth, 
and  which  in  this  world  is  about  the  only  pure  and 
unmixed  happiness. 

At  the  same  time  he  shared  Bacon's  distrust  of 
the  Aristotelian  logic  and  maintained  that  ordinary 
dialectic  is  valueless  for  those  who  desire  to  investi- 
gate the  truth  of  things.  There  is  need  of  a  method 
for  finding  out  the  truth.  He  compares  himself  to  a 
smith  forced  to  begin  at  the  beginning  by  fashion- 
ing tools  with  which  to  work. 

In  his  method  of  discovery  he  determined  to  ac- 
cept nothing  as  true  that  he  did  not  clearly  recog- 
nize to  be  so.  He  stood  against  assumptions,  and 
insisted  on  rigid  proof.  Trust  only  what  is  com- 
pletely known.  Attain  a  certitude  equal  to  that  of 
arithmetic  and  geometry.  This  attitude  of  strict 
criticism  is  characteristic  of  the  scientific  mind. 

Again,  Descartes  was  bent  on  analyzing  each  dif- 
ficulty in  order  to  solve  it ;  to  neglect  no  intermediate 
steps  in  the  deduction,  but  to  make  the  enumeration 
of  details  adequate  and  methodical.  Preserve  a  cer- 
tain order ;  do  not  attempt  to  jump  from  the  ground 
to  the  gable,  but  rise  gradually  from  what  is  simple 
and  easily  understood. 

Descartes'  interest  was  not  in  the  several  branches 
of  mathematics ;  rather  he  wished  to  establish  a  uni- 
versal mathematics,  a  general  science  relating  to 
order  and  measurement.  He  considered  all  physical 
nature,  including  the  human  body,  as  a  mechanism, 
capable  of  explanation  on  mathematical  principles. 
But  his  immediate  interest  lay  in  numerical  relation- 
ships and  geometrical  proportions. 

Recognizing  that  the  understanding  was  depend- 


84          THE  HISTORY  OF  SCIENCE 

ent  on  the  other  powers  of  the  mind,  Descartes 
resorted  in  his  mathematical  demonstrations  to  the 
use  of  lines,  because  he  could  find  no  method,  as  he 
says,  more  simple  or  more  capable  of  appealing  to 
the  imagination  and  senses.  He  considered,  how- 
ever, that  in  order  to  bear  the  relationships  in  mem- 
ory or  to  embrace  several  at  once,  it  was  essential  to 
explain  them  by  certain  formula,  the  shorter  the 
better.  And  for  this  purpose  it  was  requisite  to 
borrow  all  that  was  best  in  geometrical  analysis  and 
algebra,  and  to  correct  the  errors  of  one  by  the  other. 
Descartes  was  above  all  a  mathematician,  and  as 
such  he  may  be  regarded  as  a  forerunner  of  Newton 
and  other  scientists ;  at  the  same  time  he  developed  an 
exact  scientific  method,  which  he  believed  applicable 
to  all  departments  of  human  thought.  "  Those  long 
chains  of  reasoning,"  he  says,  "  quite  simple  and 
easy,  which  geometers  are  wont  to  employ  in  the 
accomplishment  of  their  most  difficult  demonstra- 
tions, led  me  to  think  that  everything  which  might 
fall  under  the  cognizance  of  the  human  mind  might 
be  connected  together  in  the  same  manner,  and  that, 
provided  only  one  should  take  care  not  to  receive 
anything  as  true  which  was  not  so,  and  if  one  were 
always  careful  to  preserve  the  order  necessary  for 
deducing  one  truth  from  another,  there  would  be 
none  so  remote  at  which  he  might  not  at  last  arrive, 
or  so  concealed  which  he  might  not  discover." 


SCIENTIFIC  METHOD  85 

REFERENCES 

Francis  Bacon,  Philosophical  Works  (Ellis  and  Spedding  edi- 
tion), vol.  iv,  Novum  Organum. 

J.  J.  Fahie,  Galileo;  His  Life  and  Work. 

Galileo,  Two  New  Sciences;  translated  by  Henry  Crew  and 
Alphonse  De  Salvio. 

William  Gilbert,  On  the  Loadstone ;  translated  by  P.  F.  Motte- 
lay. 

William  Harvey,  An  Anatomical  Disquisition  on  the  Motion  of 
the  Heart  and  Blood  in  Animals. 

T.  H.  Huxley,  Method  and  Results. 

D'Arcy  Power,  WiUiam  Harvey  (in  Masters  of  Medicine). 


CHAPTER  VII 

SCIENCE   AS    MEASUREMENT TYCHO    BRAKE, 

KEPLER,    BOYLE 

CONSIDERING  the  value  for  clearness  of  thought  of 
counting,  measuring  and  weighing,  it  is  not  surpris- 
ing to  find  that  in  the  seventeenth  century,  and  even 
at  the  end  of  the  sixteenth,  the  advance  of  the  sciences 
was  accompanied  by  increased  exactness  of  measure- 
ment and  by  the  invention  of  instruments  of  pre- 
cision. The  improvement  of  the  simple  microscope, 
the  invention  of  the  compound  microscope,  of  the 
telescope,  the  micrometer,  the  barometer,  the  thermo- 
scope,  the  thermometer,  the  pendulum  clock,  the 
improvement  of  the  mural  quadrant,  sextant,  spheres, 
astrolabes,  belong  to  this  period. 

Measuring  is  a  sort  of  counting,  and  weighing  a 
form  of  measuring.  We  may  count  disparate  things 
whether  like  or  unlike.  When  we  measure  or  weigh 
we  apply  a  standard  and  count  the  times  that  the  unit 
—  cubit,  pound,  hour  —  is  found  to  repeat  itself.  We 
apply  our  measure  to  uniform  extension,  meting  out 
the  waters  by  fathoms  or  space  by  the  sun's  diameter, 
and  even  subject  time  to  arbitrary  divisions.  The  hu- 
man mind  has  been  developed  through  contact  with 
the  multiplicity  of  physical  objects,  and  we  find  it 
impossible  to  think  clearly  and  scientifically  about 
our  environment  without  dividing,  weighing,  measur- 
ing, counting. 

In  measuring  time  we  cannot  rely  on  our  inward 


SCIENCE  AS  MEASUREMENT         87 

impressions ;  we  even  criticize  these  impressions  and 
speak  of  time  as  going  slowly  or  quickly.  We  are 
compelled  in  the  interests  of  accuracy  to  provide  an 
objective  standard  in  the  clock,  or  the  revolving 
earth,  or  some  other  measurable  thing.  Similarly 
with  weight  and  heat ;  we  cannot  rely  on  the  subjec- 
tive impression,  but  must  devise  apparatus  to  record 
by  a  measurable  movement  the  amount  of  the  pres- 
sure or  the  degree  of  temperature. 

"  God  ordered  all  things  by  measure,  number,  and 
weight."  The  scientific  mind  does  not  rest  satisfied 
till  it  is  able  to  see  phenomena  in  their  number  re- 
lationships. Scientific  thought  is  in  this  sense  Pythag- 
orean, that  it  inquires  in  reference  to  quantity  and 
proportion. 

As  implied  in  a  previous  chapter,  number  relations 
are  not  clearly  grasped  by  primitive  races.  Many 
primitive  languages  have  no  words  for  numerals 
higher  than  five.  That  fact  does  not  imply  that  these 
races  do  not  know  the  difference  between  large  and 
small  numbers,  but  precision  grows  with  civilization, 
with  commercial  pursuits,  and  other  activities,  such 
as  the  practice  of  medicine,  to  which  the  use  of  weights 
and  measures  is  essential.  Scientific  accuracy  is  de- 
pendent on  words  and  other  means  of  numerical  expres- 
sion. From  the  use  of  fingers  and  toes,  a  rude  score 
or  tally,  knots  on  a  string,  or  a  simple  abacus,  the 
race  advances  to  greater  refinement  of  numerical 
expression  and  the  employment  of  more  and  more 
accurate  apparatus. 

One  of  the  greatest  contributors  to  this  advance 
was  the  celebrated  Danish  astronomer,  Tycho  Brahe 
(1546-1601).  Before  1597  he  had  completed  his 


88          THE  HISTORY  OF  SCIENCE 

great  mural  quadrant  at  the  observatory  of  Urani- 
borg.  He  called  it  with  characteristic  vanity  the 
Tichonic  quadrant.  It  consisted  of  a  graduated  arc 
of  solid  polished  brass  five  inches  broad,  two  inches 
thick,  and  with  a  radius  of  about  six  and  three  quar- 
ters feet.  Each  degree  was  divided  into  minutes,  and 
each  minute  into  six  parts.  Each  of  these  parts  was 
then  subdivided  into  ten  seconds,  which  were  indi- 
cated by  dots  arranged  in  transverse  oblique  lines  on 
the  width  of  brass. 

The  arc  was  attached  in  the  observation  room  to 
a  wall  running  exactly  north,  and  so  secured  with 
screws  (firmissimis  cochleis)  that  no  force  could 
move  it.  With  its  concavity  toward  the  southern  sky 
it  was  closely  comparable,  though  reverse,  to  the 
celestial  meridian  throughout  its  length  from  horizon 
to  zenith.  The  south  wall,  above  the  point  where  the 
radii  of  the  quadrant  met,  was  pierced  by  a  cylinder 
of  gilded  brass  placed  in  a  rectangular  opening,  which 
could  be  opened  or  closed  from  the  outside.  The  ob- 
servation was  made  through  one  of  two  sights  that 
were  attached  to  the  graduated  arc  and  could  be 
moved  from  point  to  point  on  it.  In  the  sights  were 
parallel  slits,  right,  left,  upper,  lower.  If  the  alti- 
tude and  the  transit  through  the  meridian  were  to 
be  taken  at  the  same  time  the  four  directions  were  to 
be  followed.  It  was  the  practice  for  the  student  mak- 
ing the  observation  to  read  off  the  number  of  degrees, 
minutes,  etc.,  of  the  angle  at  which  the  altitude  or 
transit  was  observed,  so  that  it  might  be  recorded  by 
a  second  student.  A  third  took  the  time  from  two 
clock  dials  when  the  observer  gave  the  signal,  and  the 
exact  moment  of  observation  was  also  recorded  by 


QVADRANS     MVRALIS 

SIVE      TICHONICVS. 


THE  TICHONIC  QUADRANT 


SCIENCE  AS  MEASUREMENT         89 

student  number  two.  The  clocks  recorded  minutes 
and  the  smaller  divisions  of  time ;  great  care,  however, 
was  required  to  obtain  good  results  from  them.  There 
were  four  clocks  in  the  observatory,  of  which  the 
largest  had  three  wheels,  one  wheel  of  pure  solid  brass 
having  twelve  hundred  teeth  and  a  diameter  of  two 
cubits. 

Lest  any  space  on  the  wall  should  lie  empty  a  num- 
ber of  paintings  were  added :  Tycho  himself  in  an 
easy  attitude  seated  at  a  table  and  directing  from  a 
book  the  work  of  his  students.  Over  his  head  is  an 
automatic  celestial  globe  invented  by  Tycho  and  con- 
structed at  his  own  expense  in  1590.  Over  the  globe 
is  a  part  of  Tycho's  library.  On  either  side  are  repre- 
sented as  hanging  small  pictures  of  Tycho's  patron, 
Frederick  II  of  Denmark  (d.  1588)  and  Queen 
Sophia.  Then  other  instruments  and  rooms  of  the 
observatory  are  pictured  ;  Tycho's  students,  of  whom 
there  were  always  at  least  six  or  eight,  not  to  men- 
tion younger  pupils.  There  appears  also  his  great 
brass  globe  six  feet  in  diameter.  Then  there  is  pic- 
tured Tycho's  chemical  laboratory,  on  which  he  has 
expended  much  money.  Finally  comes  one  of  Tycho's 
hunting  dogs  —  very  faithful  and  sagacious ;  he  serves 
here  as  a  hieroglyph  of  his  master's  nobility  as  well 
as  of  sagacity  and  fidelity.  The  expert  architect  and 
the  two  artists  who  assisted  Tycho  are  delineated  in 
the  landscape  and  even  in  the  setting  sun  in  the  top- 
most part  of  the  painting,  and  in  the  decoration 
above. 

The  principal  use  of  this  largest  quadrant  was 
the  determination  of  the  angle  of  elevation  of  the 
stars  within  the  sixth  part  of  a  minute,  the  collmea- 


90          THE  HISTORY  OF  SCIENCE 

tion  being  made  by  means  of  one  of  the  sights,  the 
parallel  horizontal  slits  in  which  were  aligned  with 
the  corresponding  parts  of  the  circumference  of  the 
cylinder.  The  altitude  was  recorded  according  to 
the  position  of  the  sight  attached  to  the  graduated 
arc. 

Tycho  Brahe  had  a  great  reverence  for  Copernicus, 
but  he  did  not  accept  his  planetary  system ;  and  he 
felt  that  advance  in  astronomy  depended  on  pains- 
taking observation.  For  over  twenty  years  under  the 
kings  of  Denmark  he  had  good  opportunities  for 
pursuing  his  investigation.  The  island  of  Hven  be- 
came his  property.  A  thoroughly  equipped  observa- 
tory was  provided,  including  printing-press  and 
workshops  for  the  construction  of  apparatus.  As 
already  implied,  capable  assistants  were  at  the  as- 
tronomer's command.  In  1598,  after  having  left 
Denmark,  Tycho  in  a  splendid  illustrated  book  (As- 
tronomice  Instauratce  Mechanica)  gave  an  account  of 
this  astronomical  paradise  on  the  Insula  Venusia  as 
he  at  times  called  it.  The  book,  prepared  for  the 
hands  of  princes,  contains  about  twenty  full-page 
colored  illustrations  of  astronomical  instruments  (in- 
cluding, of  course,  the  mural  quadrant),  of  the  ex- 
terior of  the  observatory  of  Uraniborg,  etc.  The 
author  had  a  consciousness  of  his  own  worth,  and 
deserves  the  name  Tycho  the  Magnificent.  The  re- 
sults that  he  obtained  were  not  unworthy  of  the 
apparatus  employed  in  his  observations,  and  before 
he  died  at  Prague  in  1601,  Tycho  Brahe  had  con- 
signed to  the  worthiest  hands  the  painstaking  record 
of  his  labors. 

Johann  Kepler  (1571-1630)  had  been  called,  as 


SCIENCE  AS  MEASUREMENT         91 

the  astronomer's  assistant,  to  the  Bohemian  capital 
in  1600  and  in  a  few  months  fell  heir  to  Tycho's 
data  in  reference  to  777  stars,  which  he  made  the 
basis  of  the  Rudolphine  tables  of  1627.  Kepler's 
genius  was  complementary  to  that  of  his  predecessor. 
He  was  gifted  with  an  imagination  to  turn  observa- 
tions to  account.  His  astronomy  did  not  rest  in  mere 
description,  but  sought  the  physical  explanation.  He 
had  the  artist's  feeling  for  the  beauty  and  harmony, 
which  he  divined  before  he  demonstrated,  in  the 
number  relations  of  the  planetary  movements.  After 
special  studies  of  Mars  based  on  Tycho's  data,  he  set 
forth  in  1609  (Astronomia  Nemo)  (1)  that  every 
planet  moves  in  an  ellipse  of  which  the  sun  occupies 
one  focus,  and  (2)  that  the  area  swept  by  the  ra- 
dius vector  from  the  planet  to  the  sun  is  proportional 
to  the  time.  Luckily  for  the  success  of  his  investi- 
gation the  planet  on  which  he  had  concentrated  his 
attention  is  the  one  of  all  the  planets  then  known, 
the  orbit  of  which  most  widely  differs  from  a  circle. 
In  a  later  work  (Harmonica  Mundi,  1619)  the  title 
of  which,  the  Harmonics  of  the  Universe,  proclaimed 
his  inclination  to  Pythagorean  views,  he  demon- 
strated (3)  that  the  square  of  the  periodic  time  of 
any  planet  is  proportional  to  the  cube  of  its  mean 
distance  from  the  sun. 

Kepler's  studies  were  facilitated  by  the  invention, 
in  1614  by  John  Napier,  of  logarithms,  which  have 
been  said,  by  abridging  tedious  calculations,  to  dou- 
ble the  life  of  an  astronomer.  About  the  same  time 
Kepler  in  purchasing  some  wine  was  struck  by  the 
rough-and-ready  method  used  by  the  merchant  to  de- 
termine the  capacity  of  the  wine- vessels.  He  applied 


92  THE  HISTORY  OF  SCIENCE 

himself  for  a  few  days  to  the  problems  of  mensura- 
tion involved,  and  in  1615  published  his  treatise 
(Stereometria  Doliorum)  on  the  cubical  contents  of 
casks  (or  wine-jars),  a  source  of  inspiration  to  all 
later  writers  on  the  accurate  determination  of  the 
volume  of  solids.  He  helped  other  scientists  and  was 
himself  richly  helped.  As  early  as  1610  there  had 
been  presented  to  him  a  means  of  precision  of  the 
first  importance  to  the  progress  of  astronomy, 
namely,  a  Galilean  telescope. 

The  early  history  of  telescopes  shows  that  the 
effect  of  combining  two  lenses  was  understood  by 
scientists  long  before  any  particular  use  was  made  of 
this  knowledge ;  and  that  those  who  are  accredited 
with  introducing  perspective  glasses  to  the  public 
hit  by  accident  upon  the  invention.  Priority  was 
claimed  by  two  firms  of  spectacle-makers  in  Middel- 
burg,  Holland,  namely,  Zacharias,  miscalled  Jansen, 
and  Lippershey.  Galileo  heard  of  the  contrivance 
in  July,  1609,  and  soon  furnished  so  powerful  an 
instrument  of  discovery  that  things  seen  through 
it  appeared  more  than  thirty  times  nearer  and  al- 
most a  thousand  times  larger  than  when  seen  by  the 
naked  eye.  He  was  able  to  make  out  the  mountains 
in  the  moon,  the  satellites  of  Jupiter  in  rotation, 
the  spots  on  the  revolving  sun  ;  but  his  telescope 
afforded  only  an  imperfect  view  of  Saturn.  Of 
course  these  facts,  published  in  1610  (Sidereus  Nun- 
cms),  strengthened  his  advocacy  of  the  Copernican 
system.  Galileo  laughingly  wrote  Kepler  that  the 
professors  of  philosophy  were  afraid  to  look  through 
his  telescope  lest  they  should  fall  into  heresy.  The 
German  astronomer,  who  had  years  before  written 


SCIENCE  AS  MEASUREMENT         93 

on  the  optics  of  astronomy,  now  (1611)  produced 
his  Dioptrice,  the  first  satisfactory  statement  of  the 
theory  of  the  telescope. 

About  1639  Gascoigne,  a  young  Englishman,  in- 
vented the  micrometer,  which  enables  an  observer  to 
adjust  a  telescope  with  very  great  precision.  Before 
the  invention  of  the  micrometer  exactitude  was  im- 
possible, because  the  adjustment  of  the  instrument  de- 
pended on  the  discrimination  of  the  naked  eye.  The 
micrometer  was  a  further  advance  in  exact  measure- 
ment. Gascoigne's  determinations  of,  for  example, 
the  diameter  of  the  sun,  bear  comparison  with  the 
findings  of  even  recent  astronomical  science. 

The  history  of  the  microscope  is  closely  connected 
with  that  of  the  telescope.  In  the  first  half  of  the 
seventeenth  century  the  simple  microscope  came  into 
use.  It  was  developed  from  the  convex  lens,  which, 
as  we  have  seen  in  a  previous  chapter,  had  been 
known  for  centuries,  if  not  from  remote  antiquity. 
With  the  simple  microscope  Leeuwenhoek  before 
1673  had  studied  the  structure  of  minute  animal  or- 
ganisms and  ten  years  later  had  even  obtained  sight 
of  bacteria.  Very  early  in  the  same  century  Zacharias 
had  presented  Prince  Maurice,  the  commander  of  the 
Dutch  forces,  and  the  Archduke  Albert,  governor 
of  Holland,  with  compound  microscopes.  Kircher 
(1601-1680)  made  use  of  an  instrument  that  repre- 
sented microscopic  forms  as  one  thousand  times  larger 
than  their  actual  size,  and  by  means  of  the  compound 
microscope  Malpighi  was  able  in  1661  to  see  blood 
flowing  from  the  minute  arteries  to  the  minute  veins 
on  the  lung  and  on  the  distended  bladder  of  the  live 
frog.  The  Italian  microscopist  thus,  among  his  many 


94  THE  HISTORY  OF  SCIENCE 

achievements,  verified  by  observation  what  Harvey  in 
1628  had  argued  must  take  place. 

In  this  same  epoch  apparatus  of  precision  developed 
in  other  fields.  Weight  clocks  had  been  in  use  as 
time-measurers  since  the  thirteenth  century,  but  they 
were,  as  we  have  seen,  difficult  to  control  and  other- 
wise unreliable.  Even  in  the  seventeenth  century 
scientists  in  their  experiments  preferred  some  form 
of  water -clock.  In  1636  Galileo,  in  a  letter,  men- 
tioned the  feasibility  of  constructing  a  pendulum 
clock,  and  in  1641  he  dictated  a  description  of  the 
projected  apparatus  to  his  son  Vincenzo  and  to  his 
disciple  Viviani.  He  himself  was  then  blind,  and  he 
died  the  following  year.  His  instructions  were  never 
carried  into  effect.  However,  in  1657  Christian  Huy- 
gens  applied  the  pendulum  to  weight  clocks  of  the 
old  stamp.  In  1674  he  gave  directions  for  the  manu- 
facture of  a  watch,  the  movement  of  which  was 
driven  by  a  spring. 

Galileo,  to  whom  the  advance  in  exact  science  is 
so  largely  indebted,  must  also  be  credited  with  the 
first  apparatus  for  the  measurement  of  temperatures. 
This  was  invented  before  1603  and  consisted  of  a 
glass  bulb  with  a  long  stem  of  the  thickness  of  a 
straw.  The  bulb  was  first  heated  and  the  stem  placed 
in  water.  The  point  at  which  the  water,  which  rose 
in  the  tube,  might  stand  was  an  indication  of  the 
temperature.  In  1631  Jean  Rey  just  inverted  this 
contrivance,  filling  the  bulb  with  water.  Of  course 
these  thermoscopes  would  register  the  effect  of  vary- 
ing pressures  as  well  as  temperatures,  and  they  soon 
made  way  for  the  thermometer  and  the  barometer. 
Before  1641  a  true  thermometer  was  constructed  by 


SCIENCE  AS  MEASUREMENT         95 

sealing  the  top  of  the  tube  after  driving  out  the  air 
by  heat.  Spirits  of  wine  were  used  in  place  of  water. 
Mercury  was  not  employed  till  1670. 

Descartes  and  Galileo  had  brought  under  criticism 
the  ancient  idea  that  nature  abhors  a  vacuum.  They 
knew  that  the  horror  vacui  was  not  sufficient  to  raise 
water  in  a  pump  more  than  about  thirty-three  feet. 
They  had  also  known  that  air  has  weight,  a  fact 
which  soon  served  to  explain  the  so-called  force  of 
suction.  Galileo's  associate  Torricelli  reasoned  that  if 
the  pressure  of  the  air  was  sufficient  to  support  a 
column  of  water  thirty-three  feet  in  height,  it  would 
support  a  column  of  mercury  of  equal  weight.  Ac- 
cordingly in  1643  he  made  the  experiment  of  filling 
with  mercury  a  glass  tube  four  feet  long  closed  at 
the  upper  end,  and  then  opening  the  lower  end  in  a 
basin  of  mercury.  The  mercury  in  the  tube  sank  until 
its  level  was  about  thirty  inches  above  that  of  the 
mercury  in  the  basin,  leaving  a  vacuum  in  the  upper 
part  of  the  tube.  As  the  specific  gravity  of  mercury 
is  13,  Torricelli  knew  that  his  supposition  had  been 
correct  and  that  the  column  of  mercury  in  the  tube 
and  the  column  of  water  in  the  pump  were  owing  to 
the  pressure  or  weight  of  the  air. 

Pascal  thought  that  this  pressure  would  be  less 
at  a  high  altitude.  His  supposition  was  tested  on  a 
church  steeple  at  Paris,  and,  later,  on  the  Puy  de 
Dome,  a  mountain  in  Auvergne.  In  the  latter  case  a 
difference  of  three  inches  in  the  column  of  mercury 
was  shown  at  the  summit  and  base  of  the  ascent. 
Later  Pascal  experimented  with  the  siphon  and  suc- 
ceeded in  explaining  it  on  the  principle  of  atmos- 
pheric pressure. 


96          THE  HISTORY  OF  SCIENCE 

Torricelli  in  the  space  at  the  top  of  his  barometer 
(pressure-gauge)  had  produced  what  is  called  a  Tor- 
ricellian vacuum.  Otto  von  Guericke,  a  burgomaster 
of  Magdeburg,  who  had  traveled  in  France  and  Italy, 
succeeded  in  constructing  an  air-pump  by  means  of 
which  air  might  be  exhausted  from  a  vessel.  Some  of 
his  results  became  widely  known  in  1657,  though  his 
works  were  not  published  till  1673. 

Robert  Boyle  (1626-1691),  born  at  Castle  Lismore 
in  Ireland,  was  the  seventh  son  and  fourteenth  child 
of  the  distinguished  first  Earl  of  Cork.  He  was  early 
acquainted  with  these  various  experiments  in  refer- 
ence to  the  air,  as  well  as  with  Descartes'  theory  that 
air  is  nothing  but  a  congeries  or  heap  of  small,  and, 
for  the  most  part,  flexible  particles.  In  1659  he  wrote 
his  New  Experiments  Physico-Mechanical  touching 
the  Spring  of  the  Air.  Instead  of  spring,  he  at  times 
used  the  word  elater  (e\arrjp*).  In  this  treatise  he 
describes  experiments  with  the  improved  air-pump 
constructed  at  his  suggestion  by  his  assistant,  Robert 
Hooke. 

One  of  Boyle's  critics,  a  professor  at  Louvain, 
while  admitting  that  air  had  weight  and  elasticity, 
denied  that  these  were  sufficient  to  account  for  the 
results  ascribed  to  them.  Boyle  thereupon  published 
a  Defence  of  the  Doctrine  touching  the  Spring  and 
Weight  of  the  Air.  He  felt  able  to  prove  that  the 
elasticity  of  the  air  could  under  circumstances  do  far 
more  than  sustain  twenty-nine  or  thirty  inches  of 
mercury.  In  support  of  his  view  he  cited  a  recent 
experiment. 

He  had  taken  a  piece  of  strong  glass  tubing  fully 
twelve  feet  in  length.  (The  experiment  was  made 


SCIENCE  AS  MEASUREMENT         97 

by  a  well-lighted  staircase,  the  tube  being  suspended 
by  strings.)  The  glass  was  heated  more  than  a  foot 
from  the  lower  end,  and  bent  so  that  the  shorter  leg 
of  twelve  inches  was  parallel  with  the  longer.  The 
former  was  hermetically  sealed  at  the  top  and  marked 
off  in  forty-eight  quarter-inch  spaces.  Into  the  open- 
ing of  the  longer  leg,  also  graduated,  mercury  was 
poured.  At  first  only  enough  was  introduced  to  fill 
the  arch,  or  bent  part  of  the  tube  below  the  gradu- 
ated legs.  The  tube  was  then  inclined  so  that  the  air 
might  pass  from  one  leg  to  the  other,  and  equality 
of  pressure  at  the  start  be  assured.  Then  more  mer- 
cury was  introduced  and  every  time  that  the  air  in  the 
shorter  leg  was  compressed  a  half  or  a  quarter  of  an 
inch,  a  record  was  made  of  the  height  of  the  mercury 
in  the  long  leg  of  the  tube.  Boyle  reasoned  that  the 
compressed  air  was  sustaining  the  pressure  of  the 
column  of  mercury  in  the  long  leg  plus  the  pressure 
of  the  atmosphere  at  the  tube's  opening,  equivalent 
to  29  ^g-  inches  of  mercury.  Some  of  the  results  were 
as  follows :  When  the  air  in  the  short  tube  was  com- 
pressed from  12  to  3  inches,  it  was  under  a  pres- 
sure of  H7y9£  inches  of  mercury;  when  compressed 
to  4  it  was  under  pressure  of  871J  inches  of  mer- 
cury ;  when  compressed  to  6,  58  1| ;  to  9,  39|.  Of 
course,  when  at  the  beginning  of  the  experiment 
there  were  12  inches  of  air  in  the  short  tube,  it  was 
under  the  pressure  of  the  atmosphere,  equal  to  that 
of  29^-  inches  of  mercury.  Boyle  with  characteristic 
caution  was  not  inclined  to  draw  too  general  a  con- 
clusion from  his  experiment.  However,  it  was  evi- 
dent, making  allowance  for  some  slight  irregularity 
in  the  experimental  results,  that  air  reduced  under 


98  THE  HISTORY  OF  SCIENCE 

pressure  to  one  half  its  original  volume,  doubles  its 
resistance ;  and  that  if  it  is  further  reduced  to  one 
half,  —  for  example,  from  six  to  three  inches,  —  it 
has  four  times  the  resistance  of  common  air.  In  fact, 
Boyle  had  sustained  the  hypothesis  that  supposes 
the  pressures  and  expansions  to  be  in  reciprocal  pro- 
portions. 

REFERENCES 

Sir  Robert  S.  Ball,  Great  Astronomers. 

Robert  Boyle,  Works  (edited  by  Thomas  Birch). 

Sir  David  Brewster,  Martyrs  of  Science. 

J.  L.  E.  Dreyer,  Tycho  Brake. 

Sir  Oliver  Lodge,  Pioneers  of  Science. 

Flora  Masson,  Robert  Boyle  ;  a  Biography. 


CHAPTER  VIII 

COOPERATION   IN   SCIENCE THE   ROYAL 

SOCIETY 

THE  period  from  1637  to  1687  affords  a  good 
illustration  of  the  value  for  the  progress  of  science 
of  the  cooperation  in  the  pursuit  of  truth  of  men  of 
different  creeds,  nationalities,  vocations,  and  social 
ranks.  At,  or  even  before,  the  beginning  of  that 
period  the  need  of  cooperation  was  indicated  by  the 
activities  of  two  men  of  pronouncedly  social  tempera- 
ment and  interests,  namely,  the  French  Minim  father, 
Mersenne,  and  the  Protestant  Prussian  merchant, 
Samuel  Hartlib. 

Mersenne  was  a  stimulating  and  indefatigable 
correspondent.  His  letters  to  Galileo,  Jean  Rey, 
Hobbes,  Descartes,  Gassendi,  not  to  mention  other 
scientists  and  philosophers,  constitute  an  encyclo- 
pedia of  the  learning  of  the  time.  A  mathematician 
and  experimenter  himself,  he  had  a  genius  for  elicit- 
ing discussion  and  research  by  means  of  adroit  ques- 
tions. Through  him  Descartes  was  drawn  into  debate 
with  Hobbes,  and  with  Gassendi,  a  champion  of  the 
experimental  method.  Through  him  the  discoveries 
of  Harvey,  Galileo,  and  Torricelli,  as  well  as  of  many 
others,  became  widely  known.  His  letters,  in  the 
dearth  of  scientific  associations  and  the  absence  of 
scientific  periodicals,  served  as  a  general  news  agency 
among  the  learned  of  his  time.  It  is  not  surprising 
that  a  coterie  gathered  about  him  at  Paris.  Hobbes 


100        THE  HISTORY  OF  SCIENCE 

spent  months  in  daily  intercourse  with  this  group  of 
scientists  in  the  winter  of  1636-37. 

Hartlib,  though  he  scarcely  takes  rank  with  Mer- 
senne  as  a  scientist,  was  no  less  influential.  Of  a  gen- 
erous and  philanthropic  disposition,  he  repeatedly  im- 
poverished himself  in  the  cause  of  human  betterment. 
His  chief  reliance  was  on  education  and  improved 
methods  of  husbandry,  but  he  resembled  Horace 
Greeley  in  his  hospitality  to  any  project  for  the  public 
welfare. 

One  of  Hartlib's  chief  hopes  for  the  regeneration 
of  England,  if  not  of  the  whole  world,  rested  on  the 
teachings  of  the  educational  reformer  Cornenius,  a 
bishop  of  the  Moravian  Brethren.  In  1637,  Comenius 
having  shown  himself  rather  reluctant  to  put  his  most 
cherished  plans  before  the  public,  his  zealous  disciple 
precipitated  matters,  and  on  his  own  responsibility, 
and  unknown  to  Comenius,  issued  from  his  library  at 
Oxford  Preludes  to  the  Endeavors  of  Comenius.  Be- 
sides Hartlib's  preface  it  contained  a  treatise  by  the 
great  educator  on  a  Seminary  of  Christian  Pansophy, 
a  method  of  imparting  an  encyclopedic  knowledge 
of  the  sciences  and  arts. 

The  two  friends  were  followers  of  the  Baconian 
philosophy.  They  were  influenced,  as  many  others 
of  the  time,  by  the  New  Atlantis,  which  went  through 
ten  editions  between  1627  and  1670,  and  which  out- 
lined a  plan  for  an  endowed  college  with  thirty- 
six  Fellows  divided  into  groups  —  what  would  be 
called  to-day  a  university  of  research  endowed  by 
the  State.  It  is  not  surprising  to  find  Comenius 
(who  in  his  student  days  had  been  under  the  influ- 
ence of  Alsted,  author  of  an  encyclopedia  on  Baco- 


COOPERATION  IN  SCIENC  101  : 

nian  lines)  speaking  in  1638  on  the  need  of  a  collegi- 
ate society  for  carrying  on  the  educational  work  that 
he  himself  had  at  heart. 

In  1641  Hartlib  published  a  work  of  fiction  in 
the  manner  of  the  New  Atlantis,  and  dedicated  it 
to  the  Long  Parliament.  In  the  same  year  he  urged 
Comenius  to  come  to  London,  and  published  another 
work,  A  Reformation  of  Schools.  He  had  great  in- 
fluence and  did  not  hesitate  to  use  it  in  his  adoptive 
country.  Everybody  knew  Hartlib,  and  he  was  ac- 
quainted with  all  the  strata  of  English  society ;  for 
although  his  father  had  been  a  merchant,  first  in 
Poland  and  later  in  Elbing,  his  mother  was  the 
daughter  of  the  Deputy  of  the  English  Company  in 
Dantzic  and  had  relatives  of  rank  in  London,  where 
Hartlib  spent  most  of  his  life.  He  gained  the  good- 
will of  the  Puritan  Government,  and  even  after 
Cromwell's  death  was  working,  in  conjunction  with 
Boyle,  for  the  establishment  of  a  national  council  of 
universal  learning  with  Wilkins  as  president. 

When  Comenius  arrived  in  London  he  learned 
that  the  invitation  had  been  sent  by  order  of  Parlia- 
ment. This  body  was  very  anxious  to  take  up  the 
question  of  education,  especially  university  educa- 
tion. Bacon's  criticisms  of  Oxford  and  Cambridge 
were  still  borne  in  mind;  the  legislators  considered 
that  the  college  curriculum  was  in  need  of  reforma- 
tion, that  there  ought  to  be  more  fraternity  and  cor- 
respondence among  the  universities  of  Europe,  and 
they  even  contemplated  the  endowment  by  the  State 
of  scientific  experiment.  They  spoke  of  erecting  a 
university  at  London,  where  Gresham  College  had 
been  established  in  1597  and  Chelsea  College  in 


log         THE  HISTORY  OF  SCIENCE 

1610.  It  was  proposed  to  place  Gresham  College, 
the  Savoy,  or  Winchester  College,  at  the  disposition 
of  the  pan  sophists.  Comenius  thought  that  nothing 
was  more  certain  than  that  the  design  of  the  great 
Verulam  concerning  the  opening  somewhere  of  a 
universal  college,  devoted  to  the  advancement  of  the 
sciences,  could  be  carried  out.  The  impending  strug- 
gle, however,  between  Charles  I  and  the  Parliament 
prevented  the  attempt  to  realize  the  pansophic 
dream,  and  the  Austrian  Slav,  who  knew  something 
of  the  horrors  of  civil  war,  withdrew,  discouraged, 
to  the  Continent. 

Nevertheless,  Hartlib  did  not  abandon  the  cause, 
but  in  JL644  broached  Milton  on  the  subject  of  edu- 
cational reform,  and  drew  from  him  the  brief  but 
influential  tract  on  Education.  In  this  its  author 
alludes  rather  slightingly  to  Comenius,  who  had  some- 
thing of  Bacon's  infelicity  in  choice  of  titles  and  epi- 
thets and  who  must  have  seemed  outlandish  to  the 
author  of  Lycidas  and  Comus.  But  Milton  joined 
in  the  criticism  of  the  universities  —  the  study  of 
words  rather  than  things — and  advocated  an  ency- 
clopedic education  based  on  the  Greek  and  Latin 
writers  of  a  practical  and  scientific  tendency  (Aris- 
totle, Theophrastus,  Cato,  Varro,  Vitruvius,  Seneca, 
and  others).  He  outlined  a  plan  for  the  establish- 
ment of  an  institution  to  be  known  by  the  classical 
(and  Shakespearian)  name  "Academy" — a  plan 
destined  to  have  a  great  effect  on  education  in  the 
direction  indicated  by  the  friends  of  pansophia. 

In  this  same  year  Robert  Boyle,  then  an  eager 
student  of  eighteen  just  returned  to  England  from 
residence  abroad,  came  under  the  influence  of  the 


COOPERATION  IN  SCIENCE         103 

genial  Hartlib.  In  1646  he  writes  his  tutor  inquir- 
ing about  books  on  methods  of  husbandry  and  refer- 
ring to  the  new  philosophical  college,  which  valued 
no  knowledge  but  as  it  had  a  tendency  to  use.  A  few 
mouths  later  he  was  in  correspondence  with  Hartlib  in 
reference  to  the  Invisible  College,  and  had  written  a 
third  friend  that  the  corner-stones  of  the  invisible, 
or,  as  they  termed  themselves,  the  philosophical  col- 
lege, did  now  and  then  honor  him  with  their  com- 
pany. These  philosophers  whom  Boyle  entertained, 
and  whose  scientific  acumen,  breadth  of  mind,  hu- 
mility, and  universal  good-will  he  found  so  congen- 
ial, were  the  nucleus  of  the  Royal  Society  of  London, 
of  which,  on  its  definite  organization  in  1662,  he 
was  the  foremost  member.  They  had  begun  to  meet 
together  in  London  about  1645,  worthy  persons  in- 
quisitive into  natural  philosophy  —  Wilkins,  inter- 
ested in  the  navigation  of  the  air  and  of  waters  below 
the  surface  ;  Wallis,  mathematician  and  grammarian ; 
the  many-sided  Petty,  political  economist,  and  in- 
ventor of  a  double-bottomed  boat,  who  had  as  a  youth 
of  twenty  studied  with  Hobbes  in  Paris  in  1643,  and 
in  1648  was  to  write  his  first  treatise  on  industrial 
education  at  the  suggestion  of  Hartlib,  and  finally 
make  a  survey  of  Ireland  and  acquire  large  estates ; 
Foster,  professor  of  astronomy  at  Gresham  College ; 
Theodore  Haak  from  the  Pfalz ;  a  number  of  medi- 
cal men,  Dr.  Merret,  Dr.  Ent,  a  friend  of  Harvey, 
Dr.  Goddard,  who  could  always  be  relied  upon  to 
undertake  an  experiment,  Dr.  Glisson,  the  physiolo- 
gist, author  in  1654  of  a  treatise  on  the  liver  (Zte 
Hepate))  and  others.  They  met  once  a  week  at 
Goddard's  in  Wood  Street,  at  the  Bull's  Head  Tav- 
ern in  Cheapside,  and  at  Gresham  College. 


104         THE  HISTORY  OF  SCIENCE 

Dr.  Wilkins,  the  brother-in-law  of  Cromwell,  who 
is  regarded  by  some  as  the  founder  of  the  Royal 
Society,  removed  to  Oxford,  as  Warden  of  Wadham, 
in  1649.  Here  he  held  meetings  and  conducted  ex- 
periments in  conjunction  with  Wallis,  Goddard, 
Petty,  Boyle,  and  others,  including  Ward  (afterwards 
Bishop  of  Salisbury)  interested  in  Bulliau's  Astron- 
omy ;  and  the  celebrated  physician  and  anatomist, 
Thomas  Willis,  author  of  a  work  on  the  brain  (C7e- 
rebri  Anatome),  and  another  on  fevers  (JDe  Febri- 
6ws),  in  which  he  described  epidemic  typhoid  as  it 
occurred  during  the  Civil  War  in  1643. 

In  the  mean  time  the  weekly  meetings  in  London 
continued,  and  were  attended  when  convenient  by 
members  of  the  Oxford  group.  At  Gresham  College 
by  1558  it  was  the  custom  to  remain  for  discussion 
Wednesdays  and  Thursdays  after  Mr.  Wren's  lecture 
and  Mr.  Rooke's.  During  the  unsettled  state  of  the 
country  after  Cromwell's  death  there  was  some  inter- 
ruption of  the  meetings,  but  with  the  accession  of 
Charles  II  in  1660  there  came  a  greater  sense  of 
security.  New  names  appear  on  the  records,  Lord 
Brouncker,  Sir  Robert  Moray,  John  Evelyn,  Brere- 
ton,  Ball,  Robert  Hooke,  and  Abraham  Cowley. 

Plans  were  discussed  for  a  more  permanent  form 
of  organization,  especially  on  November  28,  1660, 
when  something  was  said  of  a  design  to  found  a 
college  for  the  promotion  of  physico-mathematical 
experimental  learning.  A  few  months  later  was  pub- 
lished Cowley's  proposition  for  an  endowed  college 
with  twenty  professors,  four  of  whom  should  be 
constantly  traveling  in  the  interests  of  science.  The 
sixteen  resident  professors  "  should  be  bound  to  study 


COOPERATION  IN  SCIENCE         105 

and  teach  all  sorts  of  natural,  experimental  philoso- 
phy, to  consist  of  the  mathematics,  mechanics,  medi- 
cine, anatomy,  chemistry,  the  history  of  animals, 
plants,  minerals,  elements,  etc.;  agriculture,  archi- 
tecture, art  military,  navigation,  gardening;  the 
mysteries  of  all  trades  and  improvement  of  them; 
the  facture  of  all  merchandise,  all  natural  magic  or 
divination ;  and  briefly  all  things  contained  in  the 
Catalogue  of  Natural  Histories  annexed  to  my  Lord 
Bacon's  Organon"  The  early  official  history  of  the 
Royal  Society  (Sprat,  1667)  says  that  this  proposal 
hastened  very  much  the  adoption  of  a  plan  of  organi- 
zation. Cowley  wished  to  educate  youth  and  incur 
great  expense  (<£4,000),  but  "  most  of  the  other 
particulars  of  his  draught  the  Royal  Society  is  now 
putting  in  practice." 

A  charter  of  incorporation  was  granted  in  July, 
1662 ;  and,  later,  Charles  II  proclaimed  himself 
founder  and  patron  of  the  Royal  Society  for  the  ad- 
vancement of  natural  science.  Charles  continued  to 
take  an  interest  in  this  organization,  devoted  to  the 
discovery  of  truth  by  the  corporate  action  of  men ; 
he  proposed  subjects  for  investigation,  and  asked 
their  cooperation  in  a  more  accurate  measurement 
of  a  degree  of  latitude.  He  showed  himself  tactful 
to  take  account  of  the  democratic  spirit  of  scientific 
investigation,  and  recommended  to  the  Royal  Society 
John  Graunt,  the  author  of  a  work  on  mortality  sta- 
tistics first  published  in  1661.  Graunt  was  a  shop- 
keeper of  London,  and  Charles  said  that  if  they  found 
any  more  such  tradesmen,  they  should  be  sure  to 
admit  them  all  without  more  ado. 

It  was  a  recognized  principle  of  the  Society  freely 


106         THE  HISTORY  OF  SCIENCE 

to  admit  men  of  different  religions,  countries,  pro- 
fessions. Sprat  said  that  they  openly  professed,  not 
to  lay  the  foundation  of  an  English,  Scotch,  Irish, 
Popish  or  Protestant  philosophy,  but  a  philosophy  of 
mankind.  They  sought  (hating  war  as  most  of  them 
did)  to  establish  a  universal  culture,  or,  as  they 
phrased  it,  a  constant  intelligence  throughout  all  civil 
nations.  Even  for  the  special  purposes  of  the  Society, 
hospitality  toward  all  nations  was  necessary ;  for  the 
ideal  scientist,  the  perfect  philosopher,  should  have 
the  diligence  and  inquisitiveness  of  the  northern 
nations,  and  the  cold  and  circumspect  and  wary 
disposition  of  the  Italians  and  Spaniards.  Haak 
from  the  German  Palatinate  was  one  of  the  earliest 
Fellows  of  the  Society,  and  is  even  credited  by  Wallis 
with  being  the  first  to  suggest  the  meetings  of  1645. 
Oldenburg  from  Bremen  acted  as  secretary  (along 
with  Wilkins)  and  carried  on  an  extensive  foreign 
correspondence.  Huygens  of  Holland  was  one  of  the 
original  Fellows  in  1663,  while  the  names  of  Auzout, 
Sorbiere,  the  Duke  of  Brunswick,  Bulliau,  Cassini, 
Malpighi,  Leibnitz,  Leeuwenhoek  (as  well  as  Win- 
throp  and  Roger  Williams)  appear  in  the  records  of 
the  Society  within  the  first  decade.  It  seemed  fitting 
that  this  cosmopolitan  organization  should  be  located 
in  the  world's  metropolis  rather  than  in  a  mere  uni- 
versity town.  Sprat  thought  London  the  natural  seat 
of  a  universal  philosophy. 

As  already  implied,  the  Royal  Society  was  not  ex- 
clusive in  its  attitude  toward  the  different  vocations. 
A  spirit  of  true  fellowship  prevailed  in  Gresham 
College,  as  the  Society  was  sometimes  called.  The 
medical  profession,  the  universities,  the  churches,  the 


COOPERATION  IN  SCIENCE         107 

court,  the  army,  the  navy,  trade,  agriculture,  and 
other  industries  were  there  represented.  Social  par- 
tition walls  were  broken  down,  and  the  Fellows, 
sobered  by  years  of  political  and  religious  strife, 
joined,  mutually  assisting  one  another,  in  the  advance 
of  science  for  the  sake  of  the  common  weal.  Their 
express  purpose  was  the  improvement  of  all  professions 
from  the  highest  general  to  the  lowest  artisan.  Par- 
ticular attention  was  paid  to  the  trades,  the  mechanic 
arts,  and  the  fostering  of  inventions.  One  of  their 
eight  committees  dealt  with  the  histories  of  trades ; 
another  was  concerned  with  mechanical  inventions, 
and  the  king  ordained  in  1662  that  no  mechanical 
device  should  receive  a  patent  before  undergoing 
their  scrutiny.  A  great  many  inventions  emanated 
from  the  Fellows  themselves  —  Hooke's  hygroscope ; 
Boyle's  hydrometer,  of  use  in  the  detection  of  coun- 
terfeit coin ;  and,  again,  the  tablet  anemometer  used 
by  Sir  Christopher  Wren  (the  Leonardo  da  Vinci 
of  his  age)  to  register  the  velocity  of  the  wind.  A 
third  committee  devoted  itself  to  agriculture,  and  in 
the  Society's  museum  were  collected  products  and 
curiosities  of  the  shop,  mine,  sea,  etc.  One  Fellow 
advised  that  attention  should  be  paid  even  to  the 
least  and  plainest  of  phenomena,  as  otherwise  they 
might  learn  the  romance  of  nature  rather  than  its 
true  history.  So  bent  were  they  on  preserving  a  spirit 
of  simplicity  and  straightforwardness  that  in  their 
sober  discussions  they  sought  to  employ  the  language 
of  artisans,  countrymen,  and  merchants  rather  than 
that  of  wits  and  scholars. 

Of  course  there  was  in  the  Society  a  predominance 
of  gentlemen  of  means  and  leisure,  "  free  and  uncon- 


108         THE  HISTORY  OF  SCIENCE 

fined."  Their  presence  was  thought  to  serve  a  double 
purpose.  It  checked  the  tendency  to  sacrifice  the 
search  of  truth  to  immediate  profit,  and  to  lay  such 
emphasis  on  application,  as,  in  the  words  of  a  subse- 
quent president  of  the  Society,  would  make  truth, 
and  wisdom,  and  knowledge  of  no  importance  for 
their  own  sakes.  In  the  second  place  their  presence 
was  held  to  check  dogmatism  on  the  part  of  the 
leaders,  and  subservience  on  the  part  of  their  fol- 
lowers. They  understood  how  difficult  it  is  to  trans- 
mit knowledge  without  putting  initiative  in  jeopardy 
and  that  quiet  intellect  is  easily  dismayed  in  the 
presence  of  bold  speech.  The  Society  accepted  the 
authority  of  no  one,  and  adopted  as  its  motto  Nul- 
lius  in  Verba. 

In  this  attitude  they  were  aided  by  their  subject 
and  method.  Search  for  scientific  truth  by  labora- 
tory procedure  does  not  favor  dogmatism.  The  early 
meetings  were  taken  up  with  experiments  and  dis* 
cussions.  The  Fellows  recognized  that  the  mental 
powers  are  raised  to  a  higher  degree  in  company 
than  in  solitude.  They  welcomed  diversity  of  view 
and  the  common-sense  judgment  of  the  onlooker.  As 
in  the  Civil  War  the  private  citizen  had  held  his 
own  with  the  professional  soldier,  so  here  the  con- 
tribution of  the  amateur  to  the  discussion  was  not 
to  be  despised.  They  had  been  taught  to  shun  all 
forms  of  narrowness  and  intolerance.  They  wished 
to  avoid  the  pedantry  of  the  mere  scholar,  and  the 
allied  states  of  mind  to  which  all  individuals  are  lia- 
ble ;  they  valued  the  concurring  testimony  of  the 
well-informed  assembly.  In  the  investigation  of  truth 
by  the  experimental  method  they  even  arrived  at  the 


COOPERATION  IN  SCIENCE         109 

view  that  "true  experimenting  Las  this  one  thing 
inseparable  from  it,  never  to  be  a  fixed  and  settled 
art,  and  never  to  be  limited  by  constant  rules."  In 
its  incipience  at  least  it  is  evident  that  the  Royal 
Society  was  filled  with  the  spirit  of  tolerance  and 
cooperation,  and  was  singularly  free  from  the  spirit 
of  envy  and  faction. 

Not  least  important  of  the  joint  labors  of  the  So- 
ciety were  its  publications,  which  established  con- 
tacts and  stimulated  research  throughout  the  scien- 
tific world.  Besides  the  Philosophical  Transactions, 
which,  since  their  first  appearance  in  1665,  are  the 
most  important  source  of  information  concerning  the 
development  of  modern  science,  the  Royal  Society 
printed  many  important  works,  among  which  the 
following  will  indicate  its  early  achievements :  — 

Hooke,  Robert,  M icrographia :  or  some  Physiological 
Descriptions  of  Minute  Bodies  made  by  Magnifying 
Glasses.  1665. 

Graunt,  John,  Natural  and  Political  Observations  .  .  . 
made  upon  the  Bills  of  Mortality,  with  reference  to  the 
Government,  Religion,  Trade,  Growth,  Air,  Diseases,  and 
the  several  changes  of  the  City.  3d  edition,  1665. 

Sprat,  Thomas,  The  History  of  the  Royal  Society  of  Lon- 
don, for  the  Improving  of  Natural  Knowledge.  1667. 

Malpighi,  Marcello,  Dissertatio  epistolica  de  Bombyce; 
Societati  Regies  Londini  dicata.  1669.  (On  the  silk- 
worm.) 

Evelyn,  John,  Sylva,  or  a  Discourse  of  Forest  Trees.  1670. 

Horrocks,  Jeremiah,  Opera  [Astronomica]  postuma.  1673. 

Malpighi,  Marcello,  Anatome  Plantarum.  1675. 

Willughby,  Francis,  Ornithology  (revised  by  John  Ray). 
1676. 

Evelyn,  John,  A  Philosophical  Discourse  of  Earth,  relating 
to  the  Culture  and  Improvement  of  it  for  Vegetation.  1676. 

Grew,  Nehemiah,  The  Anatomy  of  Plants.   1682. 


110         THE  HISTORY  OF  SCIENCE 

Willughby,  F.,  Historia  Piscium.   1686. 

Ray,  John,  Historia  Plantarum.  2  vols.,  1686-88. 

Flamsteed,  John,  Tide-Table  for  1687. 

Newton,  Isaac,  Philosophies  Naturalis  Principia  Mathe- 
matica.  Autore  Is.  Newton.  Imprimatur:  S.  Pepys, 
Reg.  Soc.  Prseses.  Julii  5,  1686.  4to.  Londini,  1687. 

After  the  Society  had  ordered  that  Newton's 
Mathematical  Principles  of  Natural  Philosophy 
should  be  printed,  it  was  found  that  the  funds  had 
been  exhausted  by  the  publication  of  Willughby's 
book  on  fishes.  It  was  accordingly  agreed  that  Hal- 
ley  should  undertake  the  business  of  looking  after 
it,  and  printing  it  at  his  own  charge,  which  he  had 
engaged  to  do.  Shortly  after,  the  President  of  the 
Royal  Society,  Mr.  Samuel  Pepys,  was  desired  to 
license  Mr.  Newton's  book. 

It  was  not  merely  by  defraying  the  expense  of 
publication  that  Halley  contributed  to  the  success 
of  the  Principia.  He,  Wren,  Hooke,  and  other  Fel- 
lows of  the  Royal  Society,  concluded  in  1684  that  if 
Kepler's  third  law  were  true,  then  the  attraction 
exerted  on  the  different  planets  would  vary  inversely 
as  the  square  of  the  distance.  What,  then,  would  be 
the  orbit  of  a  planet  under  a  central  attraction  vary- 
ing as  the  inverse  square  of  the  distance  ?  Halley 
found  that  Newton  had  already  determined  that  the 
form  of  the  orbit  would  be  an  ellipse.  Newton  had 
been  occupied  with  the  problem  of  gravitation  for 
about  eighteen  years,  but  until  Halley  induced  him 
to  do  so,  had  hesitated,  on  account  of  certain  unset- 
tled points,  to  publish  his  results. 

He  writes:  "I  began  (1666)  to  think  of  gravity 
extending  to  the  orb  of  the  moon,  .  .  .  and  thereby 


COOPERATION  IN  SCIENCE         111 

compared  the  force  requisite  to  keep  the  moon  in 
her  orb  with  the  force  of  gravity  at  the  surface  of 
the  earth,  and  found  them  answer  pretty  nearly." 
As  early  as  March  of  that  same  year  Hooke  had 
communicated  to  the  Society  an  account  of  experi- 
ments in  reference  to  the  force  of  gravity  at  differ- 
ent distances  from  the  surface  of  the  earth,  either 
upwards  or  downwards.  At  this  and  at  every  point 
in  Newton's  discovery  the  records  of  co-workers  are 
to  be  found. 

By  Flamsteed,  the  first  Royal  Astronomer,  were 
supplied  more  accurate  data  for  the  determination  of 
planetary  orbits.  To  Huygens  Newton  was  indebted 
for  the  laws  of  centrifugal  force.  Two  doubts  had 
made  his  meticulous  mind  pause  —  one,  of  the  ac- 
curacy of  the  data  in  reference  to  the  measurement 
of  the  meridian,  another,  of  the  attraction  of  a  spher- 
ical shell  upon  an  external  point.  In  the  first  matter 
the  Royal  Society,  as  we  have  seen,  had  been  long 
interested,  and  Picard,  who  had  worked  on  the 
measurement  of  the  earth  under  the  auspices  of  the 
Academic  des  Sciences,  brought  his  results,  which 
came  to  the  attention  of  Newton,  before  the  Royal 
Society  in  1672.  The  second  difficulty  was  solved 
by  Newton  himself  in  1685,  when  he  proved  that  a 
series  of  concentric  spherical  shells  would  act  on  an 
external  point  as  if  their  mass  were  concentrated  at 
the  center.  For  his  calculations  henceforth  the  plan- 
ets and  stars,  comets  and  all  other  bodies  are  points 
acted  on  by  lines  of  force,  and  "  Every  particle  of 
matter  in  the  universe  attracts  every  other  particle 
with  a  force  varying  inversely  as  the  square  of  their 
mutual  distances,  and  directly  as  the  mass  of  the 


THE  HISTORY  OF  SCIENCE 

attracting  particle."  He  deduced  from  this  law  that 
the  earth  must  be  flattened  at  the  poles ;  he  deter- 
mined the  orbit  of  the  moon  and  of  comets ;  he  ex- 
plained the  precession  of  the  equinoxes,  the  semi- 
diurnal tides,  the  ratio  of  the  mass  of  the  moon 
and  the  earth,  of  the  sun  and  the  earth,  etc.  No 
wonder  that  Laplace  considered  that  Newton's  Prin- 
tipia  was  assured  a  preeminence  above  all  the  other 
productions  of  the  human  intellect.  It  is  no  detrac- 
tion from  Newton's  merit  to  say  that  Halley,  Hooke, 
Wren,  Huygens,  Bulliau,  Picard,  and  many  other 
contemporaries  (not  to  mention  Kepler  and  his  pred- 
ecessors), as  well  as  the  organizations  in  which 
they  were  units,  share  the  glory  of  the  result  which 
they  cooperated  to  achieve.  On  the  contrary,  he 
seems  much  more  conspicuous  in  the  social  firma- 
ment because,  in  spite  of  the  austerity  and  seeming 
independence  of  his  genius,  he  formed  part  of  a  sys- 
tem, and  was  under  its  law. 

Shortly  after  the  founding  of  the  Royal  Society, 
correspondence,  for  which  a  committee  was  appointed, 
had  been  adopted  as  a  means  of  gaining  the  coopera- 
tion of  men  and  societies  elsewhere.  Sir  John  Moray, 
as  President,  wrote  to  Monsieur  de  Monmort,  around 
whom,  after  the  death  of  Mersenne,  the  scientific 
coterie  in  Paris  had  gathered.  This  group  of  men, 
which  toward  the  close  of  the  seventeenth  century 
regarded  itself,  not  unnaturally,  as  the  parent  soci- 
ety, was  in  1666  definitely  organized  as  the  Acad- 
emie  Royale  des  Sciences.  Finally,  Leibnitz,  who 
had  been  a  Fellow  of  the  Royal  Society  as  early  as 
1673,  and  had  spent  years  in  the  service  of  the 
Dukes  of  Brunswick,  was  instrumental  in  the  estab- 


COOPERATION  IN  SCIENCE         113 

lishraent  in  1700  of   the  Prussian  Akademie  der 
Wissenschaften  at  Berlin. 

REFERENCES 

Sir  David  Brewster,  Memoirs  of  Sir  Isaac  Newton. 

E.  Conradi,  Learned  Societies  and  Academies  in  Early  Times, 
Pedagogical  Seminary,  vol.  xii  (1905),  pp.  384-426. 

Abraham  Cowley,  A  Proposition  for  the  Advancement  of  Experi- 
mental Philosophy. 

D.  Masson,  Life  of  Milton.  Vol.  in,  chap.  n. 

Thomas  Sprat,  The  History  of  the  Royal  Society  of  London. 

The  Record  of  the  Royal  Society  (third  edition,  1912). 


CHAPTER  IX 

SCIENCE    AND    THE    STRUGGLE    FOR    LIBERTY 

BENJAMIN   FRANKLIN 

OF  the  Fellows  of  the  Royal  Society,  Benjamin 
Franklin  (1706-1790)  is  the  most  representative  of 
that  age  of  enlightenment  which  had  its  origin  in 
Newton's  Principia.  Franklin  represents  the  eight- 
eenth century  in  his  steadfast  pursuit  of  intellectual, 
social,  and  political  emancipation.  And  in  his  long 
fight,  calmly  waged,  against  the  forces  of  want,  super- 
stition, and  intolerance,  such  as  still  hamper  the  de- 
velopment of  aspiring  youth  in  America,  England, 
and  elsewhere,  he  found  science  no  mean  ally. 

There  is  some  reason  for  believing  that  the  Frank- 
lins (francus  —  free)  were  of  a  free  line,  free  from 
that  vassalage  to  an  overlord,  which  in  the  different 
countries  of  Europe  did  not  cease  to  exist  with  the 
Middle  Ages.  For  hundreds  of  years  they  had  lived 
obscurely  near  Northampton.  They  had  early  joined 
the  revolt  against  the  papal  authority.  For  gener- 
ations they  were  blacksmiths  and  husbandmen.  Frank- 
lin's great-grandfather  had  been  imprisoned  for  writ- 
ing satirical  verses  about  some  provincial  magnate. 
Of  the  grandfather's  four  sons  the  eldest  became  a 
smith,  but  having  some  ingenuity  and  scholarly  abil- 
ity turned  conveyancer,  and  was  recognized  as  able 
and  public-spirited.  The  other  three  were  dyers. 
Franklin's  father  Josiah  and  his  Uncle  Benjamin 
were  nonconformists,  and  conceived  the  plan  of  emi- 


THE  STRUGGLE  FOR  LIBERTY      115 

grating  to  America  in  order  to  enjoy  their  way  of 
religion  with  freedom. 

Benjamin,  born  at  Boston,  twenty-one  years  after 
his  father's  emigration,  was  the  youngest  of  ten  sons, 
all  of  whom  were  eventually  apprenticed  to  trades. 
The  father  was  a  man  of  sound  judgment  who  encour- 
aged sensible  conversation  in  his  home.  Uncle  Benja- 
min, who  did  not  emigrate  till  much  later,  showed 
interest  in  his  precocious  namesake.  Both  he  and  the 
maternal  grandfather  expressed  in  verse  dislike  of 
war  and  intolerance,  the  one  with  considerable  liter- 
ary skill,  the  other  with  a  good  deal  of  decent  plain- 
ness and  manly  freedom,  as  his  grandson  said. 

Benjamin  was  intended  as  a  tithe  to  the  Church, 
but  the  plan  was  abandoned  because  of  lack  of  means 
to  send  him  to  college.  After  one  year  at  the  Latin 
Grammar  School,  and  one  year  at  an  arithmetic  and 
writing  school,  for  better  or  worse,  his  education  of 
that  sort  ceased;  and  at  the  age  of  ten  he  began  to 
assist  in  his  father's  occupation,  now  that  of  tallow- 
chandler  and  soap-boiler.  He  wished  to  go  to  sea,  and 
gave  indications  of  leadership  and  enterprise.  His 
father  took  him  to  visit  the  shops  of  joiners,  brick- 
layers, turners,  braziers,  cutlers,  and  other  artisans, 
thus  stimulating  in  him  a  delight  in  handicraft.  Fi- 
nally, because  of  a  bookish  turn  he  had  been  exhibit- 
ing, the  boy  was  bound  apprentice  to  his  brother 
James,  who  about  1720  began  to  publish  the  New 
England  Courant,  the  fourth  newspaper  to  be  estab- 
lished in  America. 

Among  the  books  early  read  by  Benjamin  Frank- 
lin were  The  Pilgrim's  Progress,  certain  historical 
collections,  a  book  on  navigation,  works  of  Protestant 


116         THE  HISTORY  OF  SCIENCE 

controversy,  Plutarch's  Lives,  filled  with  the  spirit 
of  Greek  freedom,  Dr.  Mather's  Bonifacius,  and 
Defoe's  Essay  on  Projects.  The  last  two  seemed  to 
give  him  a  way  of  thinking,  to  adopt  Franklin's 
phraseology,  that  had  an  influence  on  some  of  the 
principal  events  of  his  life.  Defoe,  an  ardent  non- 
conformist, educated  in  one  of  the  Academies  (estab- 
lished on  Milton's  model)  and  especially  trained  in 
English  and  current  history,  advocated  among  other 
projects  a  military  academy,  an  academy  for  improv- 
ing the  vernacular,  and  an  academy  for  women.  He 
thought  it  barbarous  that  a  civilized  and  Christian 
country  should  deny  the  advantages  of  learning  to 
women.  They  should  be  brought  to  read  books  and 
especially  history.  Defoe  could  not  think  that  God 
Almighty  had  made  women  so  glorious,  with  souls 
capable  of  the  same  accomplishments  with  men,  and 
all  to  be  only  stewards  of  our  houses,  cooks,  and 
slaves. 

Benjamin  still  had  a  hankering  for  the  sea,  but  he 
recognized  in  the  printing-office  and  access  to  books 
other  means  of  escape  from  the  narrowness  of  the 
Boston  of  1720.  Between  him  and  another  bookish 
boy,  John  Collins,  arose  an  argument  in  reference  to 
the  education  of  women.  The  argument  took  the  form 
of  correspondence.  Josiah  Franklin's  judicious  criti- 
cism led  Benjamin  to  undertake  the  well-known  plan 
of  developing  his  literary  style. 

Passing  over  his  reading  of  the  Spectator,  however, 
it  is  remarkable  how  soon  his  mind  sought  out  and 
assimilated  its  appropriate  nourishment,  Locke's  Es- 
say on  the  Human  Understanding,  which  began  the 
modern  epoch  in  psychology ;  the  Port  Royal  Logic, 


THE  STRUGGLE  FOR  LIBERTY      117 

prepared  by  that  brilliant  group  of  noble  Catholics 
about  Pascal ;  the  works  of  Locke's  disciple  Collins, 
whose  Discourse  on  Freethinking  appeared  in  1713; 
the  ethical  writings  (1708-1713)  of  Shaftesbury, 
who  defended  liberty  and  justice,  and  detested  all 
persecution.  A  few  pages  of  translation  of  Xeno- 
phon's  Memorabilia  gave  him  a  hint  as  to  Socrates' 
manner  of  discussion,  and  he  made  it  his  own,  and 
avoided  dogmatism. 

Franklin  rapidly  became  expert  as  a  printer,  and 
early  contributed  articles  to  the  paper.  His  brother, 
however,  to  whom  he  had  been  bound  apprentice  for 
a  period  of  nine  years,  humiliated  and  beat  him. 
Benjamin  thought  that  the  harsh  and  tyrannical 
treatment  he  received  at  this  time  was  the  means  of 
impressing  him  with  that  aversion  to  arbitrary  power 
that  stuck  to  him  through  his  whole  life.  He  had  a 
strong  desire  to  escape  from  his  bondage,  and,  after 
five  years  of  servitude,  found  the  opportunity.  James 
Franklin,  on  account  of  some  offensive  utterances  in 
the  New  England  Courant,  was  summoned  before 
the  Council  and  sent  to  jail  for  one  month,  during 
which  time  Benjamin,  in  charge  of  the  paper,  took 
the  side  of  his  brother  and  made  bold  to  give  the 
rulers  some  rubs.  Later,  James  was  forbidden  to  pub- 
lish the  paper  without  submitting  to  the  supervision 
of  the  Secretary  of  the  Province.  To  evade  the  diffi- 
culty the  New  England  Courant  was  published  in 
Benjamin's  name,  James  announcing  his  own  retire- 
ment. In  fear  that  this  subterfuge  might  be  chal- 
lenged, he  gave  Benjamin  a  discharge  of  his  inden- 
tures, but  at  the  same  time  signed  with  him  a  new 
secret  contract.  Fresh  quarrels  arose  between  the 


118         THE  HISTORY  OF  SCIENCE 

brothers,  however,  and  Benjamin,  knowing  that  the 
editor  dared  not  plead  before  court  the  second  con- 
tract, took  upon  himself  to  assert  his  freedom,  a  step 
which  he  later  regretted  as  not  dictated  by  the  high- 
est principle. 

Unable  to  find  other  employment  in  Boston,  con- 
demned by  his  father's  judgment  in  the  matter  of  the 
contract,  somewhat  under  public  criticism  also  for  his 
satirical  vein  and  heterodoxy,  Franklin  determined  to 
try  his  fortunes  elsewhere.  Thus,  at  the  age  of  sev- 
enteen he  made  his  escape  from  Boston. 

Unable  to  find  work  in  New  York,  he  arrived 
after  some  difficulties  in  Philadelphia  in  October, 
1723.  He  had  brought  no  recommendations  from 
Boston;  his  supply  of  money  was  reduced  to  one 
Dutch  dollar  and  a  shilling  in  copper.  But  he  that 
hath  a  Trade  hath  an  Estate  (as  Poor  Richard 
says).  His  capital  was  his  industry,  his  skill  as  a 
printer,  his  good-will,  his  shrewd  powers  of  observa- 
tion, his  knowledge  of  books,  and  ability  to  write. 
Franklin,  recognized  as  a  promising  young  man  by 
the  Governor,  Sir  William  Keith,  as  previously  by 
Governor  Burnet  of  New  York,  had  a  growing  sense 
of  personal  freedom  and  self-reliance. 

But  increased  freedom  for  those  who  deserve  it 
means  increased  responsibility ;  for  it  implies  the 
possibility  of  error.  Franklin,  intent  above  all 
on  the  wise  conduct  of  life,  was  deeply  perturbed 
in  his  nineteenth  and  twentieth  years  by  a  premature 
engagement,  in  which  his  ever-passionate  nature  had 
involved  him,  by  his  failure  to  pay  over  money  col- 
lected for  a  friend,  and  by  the  unsettled  state  of  his 
religious  and  ethical  beliefs.  Encouraged  by  Keith 


THE  STRUGGLE  FOR  LIBERTY      119 

to  purchase  the  equipment  for  an  independent  print- 
ing-office, Franklin,  though  unable  to  gain  his  fa- 
ther's support  for  the  project,  went  to  London  (for 
the  ostensible  purpose  of  selecting  the  stock)  at  the 
close  of  the  year  1724. 

He  remained  in  London  a  year  and  a  half,  working 
in  two  of  the  leading  printing  establishments  of  the 
metropolis,  where  his  skill  and  reliability  were  soon 
prized.  He  found  the  English  artisans  of  that  time 
great  guzzlers  of  beer,  and  influenced  some  of  his 
co-workers  to  adopt  his  own  more  abstinent  and  hygi- 
enic habits  of  eating  and  drinking.  About  this  time 
a  book,  Religion  of  Nature  Delineated,  by  William 
Wollaston  (great-grandfather  of  the  scientist  Wol- 
laston)  so  roused  Franklin's  opposition  that  he  wrote 
a  reply,  which  he  printed  in  pamphlet  form  before 
leaving  London  in  1726,  and  the  composition  of 
which  he  afterwards  regretted. 

He  returned  to  Philadelphia  in  the  employ  of  a 
Quaker  merchant,  on  whose  death  he  resumed  work 
as  printer  under  his  former  employer.  He  was  given 
control  of  the  office,  undertook  to  make  his  own  type, 
contrived  a  copper-plate  press,  the  first  in  America, 
and  printed  paper  money  for  New  Jersey.  The  sub- 
stance of  some  lectures  in  defense  of  Christianity,  in 
courses  endowed  by  the  will  of  Robert  Boyle,  made 
Franklin  a  Deist.  At  the  same  time  his  views  on 
moral  questions  were  clarified,  and  he  came  to  recog- 
nize that  truth,  sincerity,  and  integrity  were  of  the 
utmost  importance  to  the  felicity  of  life.  What  he 
had  attained  by  his  own  independent  thought  ren- 
dered him  ultimately  more  careful  rather  than  more 
reckless.  He  now  set  value  on  his  own  character,  and 
resolved  to  preserve  it. 


120         THE  HISTORY  OF  SCIENCE 

In  1727,  still  only  twenty-one,  he  drew  together  a 
number  of  young  men  in  a  sort  of  club,  called  the 
"  Junto,"  for  mutual  benefit  in  business  and  for  the 
discussion  of  morals,  politics,  and  natural  philosophy. 
They  professed  tolerance,  benevolence,  love  of  truth. 
They  discussed  the  effect  on  business  of  the  issue  of 
paper  money,  various  natural  phenomena,  and  kept 
a  sharp  look-out  for  any  encroachment  on  the  rights 
of  the  people.  It  is  not  unnatural  to  find  that  in  a 
year  or  two  (1729),  after  Franklin  and  a  friend  had 
established  a  printing  business  of  their  own  and  ac- 
quired the  Pennsylvania  Gazette,  the  young  poli- 
tician championed  the  cause  of  the  Massachusetts 
Assembly  against  the  claims  first  put  forward  by 
Governor  Burnet,  and  that  he  used  spirited  language 
referring  to  America  as  a  nation  and  clime  foreign 
to  England. 

In  1730  Franklin  bought  out  his  partner,  and  in 
the  same  year  published  dialogues  in  the  Socratic 
manner  in  reference  to  virtue  and  pleasure,  which 
show  a  rapid  development  in  his  general  views. 
About  the  same  time  he  married,  restored  the  money 
that  had  long  been  owing,  and  formulated  his  ethical 
code  and  religious  creed.  He  began  in  1732  the  Poor 
Richard  Almanacks,  said  to  offer  in  their  homely 
wisdom  the  best  course  in  existence  in  practical 
morals. 

As  early  as  1729  Franklin  had  published  a  pam- 
phlet on  Paper  Currency.  It  was  a  well-reasoned 
discussion  on  the  relation  of  the  issue  of  paper  cur- 
rency to  rate  of  interest,  land  values,  manufactures, 
population,  and  wages.  The  want  of  money  discour- 
aged laboring  and  handicraftsmen.  One  must  con- 


THE  STRUGGLE  FOR  LIBERTY      121 

sider  the  nature  and  value  of  money  in  general. 
This  essay  accomplished  its  purpose  in  the  Assembly. 
It  was  the  first  of  those  contributions  which,  arising 
from  Franklin's  consideration  of  the  social  and  indus- 
trial circumstances  of  the  times,  gained  for  him  recog- 
nition as  the  first  American  economist.  It  was  in  the 
same  spirit  that  in  1751  he  discussed  the  question  of 
population  after  the  passage  of  the  British  Act  for- 
bidding the  erection  or  the  operation  of  iron  or  steel 
mills  in  the  colonies.  Science  for  Franklin  was  no 
extraneous  interest;  he  was  all  of  a  piece,  and  it 
was  as  a  citizen  of  Philadelphia  he  wrote  those  essays 
that  commanded  the  attention  of  Adam  Smith, 
Malthus,  and  Turgot. 

In  1731  he  was  instrumental  in  founding  the  first 
of  those  public  libraries,  which  (along  with  a  free 
press)  have  made  American  tradesmen  and  farmers 
as  intelligent,  in  Franklin's  judgment,  as  most  gen- 
tlemen from  other  countries,  and  contributed  to  the 
spirit  with  which  they  defended  their  liberties.  The 
diffusion  of  knowledge  became  so  general  in  the 
colonies  that  in  1766  Franklin  was  able  to  tell  the 
English  legislators  that  the  seeds  of  liberty  were 
universally  found  there  and  that  nothing  could  erad- 
icate them.  Franklin  became  clerk  of  the  General 
Assembly  and  postmaster,  improved  the  paving  and 
lighting  of  the  city  streets,  and  established  the  first 
fire  brigade  and  the  first  police  force  in  America. 
Then  in  1743  in  the  same  spirit  of  public  benefi- 
cence Franklin  put  forth  his  Proposal  for  Promot- 
ing Useful  Knowledge  among  the  British  Plan- 
tations in  America.  It  outlines  his  plan  for  the 
establishment  of  the  American  Philosophical  Society. 


THE   HISTORY  OF  SCIENCE 

Correspondence  had  already  been  established  with 
the  Royal  Society  of  London.  It  is  not  diffi- 
cult to  see  in  Franklin  the  same  spirit  that  had  ani- 
mated Hartlib,  Boyle,  Petty,1  Wilkins,  and  their 
friends  one  hundred  years  before.  In  fact,  Franklin 
was  the  embodiment  of  that  union  of  scientific  ideas 
and  practical  skill  in  the  industries  that  with  them 
was  merely  a  pious  wish. 

In  this  same  year  of  1743  an  eclipse  of  the  moon, 
which  could  not  be  seen  at  Philadelphia  on  account 
of  a  northeast  storm,  was  yet  visible  at  Boston, 
where  the  storm  came,  as  Franklin  learned  from  his 
brother,  about  an  hour  after  the  time  of  observation. 
Franklin,  who  knew  something  of  fireplaces,  ex- 
plained the  matter  thus :  "  When  I  have  a  fire  in 
my  chimney,  there  is  a  current  of  air  constantly 
flowing  from  the  door  to  the  chimney,  but  the  be- 
ginning of  the  motion  was  at  the  chimney."  So  in 
a  mill-race,  water  stopped  by  a  gate  is  like  air  in  a 
calm.  When  the  gate  is  raised,  the  water  moves  for- 
ward, but  the  motion,  so  to  speak,  runs  backward. 
Thus  the  principle  was  established  in  meteorology 
that  northeast  storms  arise  to  the  southwest. 

No  doubt  Franklin  was  not  oblivious  of  the  prac- 
tical value  of  this  discovery,  for,  as  Sir  Humphry 
Davy  remarked,  he  in  no  instance  exhibited  that 
false  dignity,  by  which  philosophy  is  kept  aloof  from 
common  applications.  In  fact,  Franklin  was  rather 
apologetic  in  reference  to  the  magic  squares  and 

1  See  The  Advice  of  W.  P.  to  Mr.  Samuel  Hartlib  for  the  Ad- 
vancement of  some  Particular  Parts  of  Learning,  in  which  is  advo- 
cated a  Gymnasium  Mechanicum  or  a  College  of  Tradesmen  with 
fellowships  for  experts.  Petty  wanted  trade  encyclopedias  pre- 
pared, and  hoped  for  inventions  in  abundance. 


THE  STRUGGLE  FOR  LIBERTY      123 

circles,  with  which  he  sometimes  amused  his  leisure, 
as  a  sort  of  ingenious  trifling.  At  the  very  time 
that  the  question  of  the  propagation  of  storms  arose 
in  his  mind  he  had  contrived  the  Pennsylvania  fire- 
place, which  was  to  achieve  cheap,  adequate,  and 
uniform  heating  for  American  homes.  His  aspira- 
tion was  for  a  free  people,  well  sheltered,  well  fed, 
well  clad,  well  instructed. 

In  1747  Franklin  made  what  is  generally  consid- 
ered his  chief  contribution  to  science.  One  of  his 
correspondents,  Collinson  (a  Fellow  of  the  Royal 
Society  and  a  botanist  interested  in  useful  plants, 
through  whom  the  vine  was  introduced  into  Vir- 
ginia), had  sent  to  the  Library  Company  at  Phila- 
delphia one  of  the  recently  invented  Leyden  jars 
with  instructions  for  its  use.  Franklin,  who  had 
already  seen  similar  apparatus  at  Boston,  and  his 
friends,  set  to  work  experimenting.  For  months  he 
had  leisure  for  nothing  else.  In  this  sort  of  activity 
he  had  a  spontaneous  and  irrepressible  delight.  By 
March,  1747,  they  felt  that  they  had  made  discov- 
eries, and  in  July,  and  subsequently,  Franklin  re- 
ported results  to  Collinson.  He  had  observed  that  a 
pointed  rod  brought  near  the  jar  was  much  more 
efficacious  than  a  blunt  rod  in  drawing  off  the 
charge ;  also  that  if  a  pointed  rod  were  attached  to 
the  jar,  the  charge  would  be  thrown  off,  and  accu- 
mulation of  charge  prevented.  Franklin,  moreover, 
found  that  the  nature  of  the  charges  on  the  inside 
and  on  the  outside  of  the  glass  was  different.  He 
spoke  of  one  as  plus  and  the  other  as  minus.  Again, 
"  We  say  B  (and  bodies  like-circumstanced)  is 
electricized  positively;  A  negatively."  Dufay  had 


124         THE  HISTORY  OF  SCIENCE 

recognized  two  sorts  of  electricity,  obtained  by  rub- 
bing a  glass  rod  and  a  stick  of  resin,  and  had 
spoken  of  them  as  vitreous  and  resinous.  For  Frank- 
lin electricity  was  a  single  subtle  fluid,  and  electrical 
manifestations  were  owing  to  the  degree  of  its  pres- 
ence, to  interruption  or  restoration  of  equilibrium. 

His  mind,  however,  was  bent  on  the  use,  the  ap- 
plications, the  inventions,  to  follow.  He  contrived 
an  "  electric  jack  driven  by  two  Leyden  jars  and 
capable  of  carrying  a  large  fowl  with  a  motion  fit 
for  roasting  before  a  fire."  He  also  succeeded  in 
driving  an  "  automatic  "  wheel  by  electricity,  but  he 
regretted  not  being  able  to  turn  his  discoveries  to 
greater  account. 

He  thought  later  —  in  1748  —  that  there  were 
many  points  of  similarity  between  lightning  and  the 
spark  from  a  Leyden  jar,  and  suggested  an  experi- 
ment to  test  the  identity  of  their  natures.  The  sug- 
gestion was  acted  upon  at  Marly  in  France.  An  iron 
rod  about  forty  feet  long  and  sharp  at  the  end  was 
placed  upright  in  the  hope  of  drawing  electricity 
from  the  storm-clouds.  A  man  was  instructed  to 
watch  for  storm-clouds,  and  to  touch  a  brass  wire, 
attached  to  a  glass  bottle,  to  the  rod.  The  conditions 
seemed  favorable  May  10,  1752 ;  sparks  between 
the  wire  and  rod  and  a  "  sulphurous "  odor  were 
perceived  (the  manifestations  of  wrath !).  Franklin's 
well-known  kite  experiment  followed.  In  1753  he 
received  from  the  Royal  Society  a  medal  for  the 
identification  and  control  of  the  forces  of  lightning ; 
subsequently  he  was  elected  Fellow,  became  a  mem- 
ber of  the  Academic  des  Sciences,  and  of  other 
learned  bodies.  By  1782  there  were  as  many  as  four 


THE  STRUGGLE  FOR  LIBERTY      125 

hundred  lightning  rods  in  use  in  Philadelphia  alone, 
though  some  conservative  people  regarded  their  em- 
ployment as  impious.  Franklin's  good-will,  clearness 
of  conception,  and  common  sense  triumphed  every- 
where. 

One  has  only  to  recall  that  in  1753  he  (along 
with  Hunter)  was  in  charge  of  the  postal  service  of 
the  colonies,  that  in  1754  as  delegate  to  the  Albany 
Convention  he  drew  up  the  first  plan  for  colonial 
union,  and  that  in  the  following  year  he  furnished 
Braddock  with  transportation  for  the  expedition 
against  Fort  Duquesne,  to  realize  the  distractions 
amid  which  he  pursued  science.  In  1748  he  had 
sold  his  printing  establishment  with  the  purpose  of 
devoting  himself  to  physical  experiment,  but  the 
conditions  of  the  time  saved  him  from  specialization. 

In  1749  he  drew  up  proposals  relating  to  the 
education  of  youth  in  Pennsylvania,  which  led,  two 
years  later,  to  the  establishment  of  the  first  Ameri- 
can Academy.  His  plan  was  so  advanced,  so  demo- 
cratic, springing  as  it  did  from  his  own  experience, 
that  no  secondary  school  has  yet  taken  full  advan- 
tage of  its  wisdom.  The  school,  chartered  in  1753, 
grew  ultimately  into  the  University  of  Pennsylvania. 
Moreover,  it  became  the  prototype  of  thousands  of 
schools,  which  departed  from  the  Latin  Grammar 
Schools  and  the  Colleges  by  the  introduction  of  the 
sciences  and  practical  studies  into  the  curriculum. 

Franklin  deserves  mention  not  only  in  connection 
with  economics,  meteorology,  practical  ethics,  elec- 
tricity, and  pedagogy ;  his  biographer  enumerates 
nineteen  sciences  to  which  he  made  original  contri- 
butions or  which  he  advanced  by  intelligent  criti- 


126        THE  HISTORY  OF  SCIENCE 

cism.  In  medicine  he  invented  bifocal  lenses  and 
founded  the  first  American  public  hospital ;  in  navi- 
gation he  studied  the  Gulf  Stream  and  waterspouts, 
and  suggested  the  use  of  oil  in  storms  and  the  con- 
struction of  ships  with  water-tight  compartments; 
in  agriculture  he  experimented  with  plaster  of  Paris 
as  a  fertilizer  and  introduced  in  America  the  use  of 
rhubarb  ;  in  chemistry  he  aided  Priestley's  experi- 
ments by  information  in  reference  to  marsh  gas.  He 
foresaw  the  employment  of  air  craft  in  war.  Think- 
ing the  English  slow  to  take  up  the  interest  in  bal- 
loons, he  wrote  that  we  should  not  suffer  pride  to 
prevent  our  progress  in  science.  Pride  that  dines  on 
vanity  sups  on  contempt,  as  Poor  Richard  says. 
When  it  was  mentioned  in  his  presence  that  birds 
fly  in  inclined  planes,  he  launched  a  half  sheet  of 
paper  to  indicate  that  his  previous  observations  had 
prepared  his  mind  to  respond  readily  to  the  discov- 
ery. His  quickness  and  versatility  made  him  sought 
after  by  the  best  intellects  of  Europe. 

I  pass  over  his  analysis  of  mesmerism,  his  con- 
ception of  light  as  dependent  (like  lightning)  on  a 
subtle  fluid,  his  experiments  with  colored  cloths,  his 
view  of  the  nature  of  epidemic  colds,  interest  in  in- 
oculation for  smallpox,  in  ventilation,  vegetarianism, 
a  stove  to  consume  its  own  smoke,  the  steamboat, 
and  his  own  inventions  (clock,  harmonica,  etc.),  for 
which  he  refused  to  take  out  patents. 

However,  from  the  many  examples  of  his  scien- 
tific acumen  I  select  one  more.  As  early  as  1747  he 
had  been  interested  in  geology  and  had  seen  speci- 
mens of  the  fossil  remains  of  marine  shells  from  the 
strata  of  the  highest  parts  of  the  Alleghany  Moun- 


THE  STRUGGLE  FOR  LIBERTY      127 

tains.  Later  he  stated  that  either  the  sea  had  once 
stood  at  a  higher  level,  or  that  these  strata  had  been 
raised  by  the  force  of  earthquakes.  Such  convul- 
sions of  nature  are  not  wholly  injurious,  since,  by 
bringing  a  great  number  of  strata  of  different  kinds 
to  day,  they  have  rendered  the  earth  more  fit  for 
use,  more  capable  of  being  to  mankind  a  convenient 
and  comfortable  habitation.  He  thought  it  unlikely 
that  a  great  bouleversement  should  happen  if  the 
earth  were  solid  to  the  center.  Rather  the  surface  of 
the  globe  was  a  shell  resting  on  a  fluid  of  very  great 
specific  gravity,  and  was  thus  capable  of  being  broken 
and  disordered  by  violent  movement.  As  late  as 
1788  Franklin  wrote  his  queries  and  conjectures 
relating  to  magnetism  and  the  theory  of  the  earth. 
Did  the  earth  become  magnetic  by  the  development 
of  iron  ore  ?  Is  not  magnetism  rather  interplanetary 
and  interstellar  ?  May  not  the  near  passing  of  a 
comet  of  greater  magnetic  force  than  the  earth  have 
been  a  means  of  changing  its  poles  and  thereby 
wrecking  and  deranging  its  surface,  and  raising  and 
depressing  the  sea  level  ? 

We  are  not  here  directly  concerned  with  his  polit- 
ical career,  in  his  checking  of  governors  and  propri- 
etaries, in  his  activities  as  the  greatest  of  American 
diplomats,  as  the  signer  of  the  Declaration  of  In- 
dependence, of  the  Treaty  of  Versailles,  and  of  the 
American  Constitution,  nor  as  the  president  of  the 
Supreme  Executive  Council  of  Pennsylvania  in  his 
eightieth,  eighty-first,  and  eighty-second  years.  When 
he  was  eighty-four,  as  president  of  the  Society  for 
Promoting  the  Abolition  of  Slavery,  he  signed  a 
petition  to  Congress  against  that  atrocious  debase- 


128         THE  HISTORY  OF  SCIENCE 

ment  of  human  nature,  and  six  weeks  later,  within 
a  few  weeks  of  his  death,  defended  the  petition  with 
his  accustomed  vigor,  humor,  wisdom,  and  ardent 
love  of  liberty.  Turgot  wittily  summed  up  Frank- 
lin's career  by  saying  that  he  had  snatched  the  light- 
ning from  the  heavens  and  the  scepter  from  the 
hands  of  tyrants  (eripuit  coelo  fulmen  sceptrumque 
tyrannis) ;  for  both  his  political  and  scientific  ac- 
tivities sprang  from  the  same  impelling  emotion  — 
hatred  of  the  exercise  of  arbitrary  power  and  desire 
for  human  welfare.  It  is  no  wonder  that  the  French 
National  Assembly,  promulgators  of  the  Rights  of 
Man,  paused  in  their  labors  to  pay  homage  to  the 
simple  citizen,  who,  representing  America  in  Paris 
from  his  seventy-first  till  his  eightieth  year,  had  by 
his  wisdom  and  urbanity  illustrated  the  best  fruits 
of  an  instructed  democracy. 

REFERENCES 

American  Philosophical  Society,  Record  of  the  Celebration  of  the 
Two  Hundredth  Anniversary  of  the  Birth  of  Benjamin  Franklin. 

S.  G.  Fisher,  The  True  Benjamin  Franklin. 

Paul  L.  Ford,  Many-sided  Franklin. 

Benjamin  Franklin,  Complete  Works,  edited  by  A.  H.  Smyth, 
ten  volumes,  vol.  x  containing  biography. 


CHAPTER  X 

THE  INTERACTION  OF  THE    SCIENCES WERNER, 

BUTTON,    BLACK,    HALL,    WILLIAM    SMITH 

THE  view  expressed  by  Franklin  regarding  the 
existence  of  a  fiery  mass  underlying  the  crust  of  the 
earth  was  not  in  his  time  universally  accepted.  In 
fact,  it  was  a  question  very  vigorously  disputed  what 
part  the  internal  or  volcanic  fire  played  in  the  for- 
mation and  modification  of  rock  masses.  Divergent 
views  were  represented  by  men  who  had  come  to 
the  study  of  geology  with  varying  aims  and  diverse 
scientific  schooling,  and  the  advance  of  the  science 
of  the  earth's  crust  was  owing  in  no  small  measure 
to  the  interaction  of  the  different  sciences  which  the 
exponents  of  the  various  points  of  view  brought  to 
bear. 

Abraham  Gottlob  Werner  (1750-1817)  was  the 
most  conspicuous  and  influential  champion  on  the 
side  of  the  argument  opposed  to  the  acceptance  of 
volcanic  action  as  one  of  the  chief  causes  of  geologic 
formations.  He  was  born  in  Saxony  and  came  of  a 
family  which  had  engaged  for  three  hundred  years 
in  mining  and  metal  working.  They  were  active  in 
Saxony  when  George  Agricola  prepared  his  famous 
works  on  metallurgy  and  mineralogy  inspired  by  the 
traditional  wisdom  of  the  local  iron  industry.  Wer- 
ner's father  was  an  overseer  of  iron-works,  and  fur- 
nished his  son  with  mineral  specimens  as  playthings 
before  the  child  could  pronounce  their  names.  In 


130         THE  HISTORY  OF  SCIENCE 

1769  Werner  was  invited  to  attend  the  newly 
founded  Bergakademie  (School  of  Mines)  at  Frei- 
berg. Three  years  later  he  went  to  the  University 
of  Leipzig,  but,  true  to  his  first  enthusiasm,  wrote 
in  1774  concerning  the  outward  characteristics  of 
minerals  (Von  den  ausserlichen  Kennzeichen  der 
Fossilien).  The  next  year  he  was  recalled  to  Frei- 
berg as  teacher  of  mineralogy  and  curator  of  collec- 
tions. He  was  intent  on  classification,  and  might  be 
compared  in  that  respect  with  the  naturalist  Buff  on, 
or  the  botanist  Linnaeus.  He  knew  that  chemistry 
afforded  a  surer,  but  slower,  procedure ;  his  was  a 
practical,  intuitive,  field  method.  He  observed  the 
color,  the  hardness,  weight,  fracture  of  minerals,  and 
experienced  the  joy  the  youthful  mind  feels  in  rapid 
identification.  He  translated  Cronstedt's  book  on 
mineralogy  descriptive  of  the  practical  blow-pipe 
tests.  After  the  identification  of  minerals,  Werner 
was  interested  in  their  discovery,  the  location  of 
deposits,  their  geographical  distribution,  and  the  rel- 
ative positions  of  different  kinds  of  rocks,  especially 
the  constant  juxtaposition  or  superposition  of  one 
stratum  in  relation  to  another. 

Werner  was  an  eloquent,  systematic  teacher  with 
great  charm  of  manner.  He  kept  in  mind  the  prac- 
tical purposes  of  mining,  and  soon  people  flocked  to 
Freiberg  to  hear  him  from  all  the  quarters  of  Europe. 
He  had  before  long  disciples  in  every  land.  He  saw 
all  phenomena  from  the  standpoint  of  the  geologist. 
He  knew  the  medicinal,  as  well  as  the  economic, 
value  of  minerals.  He  knew  the  relation  of  the  soil 
to  the  rocks,  and  the  effects  of  both  on  racial  char- 
acteristics. Building-stone  determines  style  of  archi- 


INTERACTION  OF  THE  SCIENCES    131 

tecture.  Mountains  and  river-courses  have  bearing 
on  military  tactics.  He  turned  his  linguistic  knowl- 
edge to  account  and  furnished  geology  with  a  defi- 
nite nomenclature.  Alex.  v.  Humboldt,  Robert  Jame- 
son, D'Aubuisson,  Weiss  (the  teacher  of  Froebel), 
were  among  his  students.  Crystallography  and  min- 
eralogy became  the  fashion.  Goethe  was  among  the 
enthusiasts,  and  philosophers  like  Schelling,  under 
the  spell  of  the  new  science,  almost  deified  the  phys- 
ical universe. 

Werner  considered  all  rocks  as  having  originated 
by  crystallization,  either  chemical  or  mechanical, 
from  an  aqueous  solution  —  a  universal  primitive 
ocean.  He  was  a  Neptunist,  as  opposed  to  the  Vul- 
can ists  or  Plutonists,  who  believed  in  the  existence 
of  a  central  fiery  mass.  Werner  thought  that  the 
earth  showed  universal  strata  like  the  layers  of  an 
onion,  the  mountains  being  formed  by  erosion,  sub- 
sidence, cavings-in.  In  his  judgment  granite  was  a 
primitive  rock  formed  previous  to  animal  and  vege- 
table life  (hence  without  organic  remains)  by  chem- 
ical precipitation.  Silicious  slate  was  formed  later 
by  mechanical  crystallization.  At  this  period  organ- 
ized fossils  first  appear.  Sedimentary  rocks,  like  old 
red  sandstone,  and,  according  to  Werner,  basalt, 
are  in  a  third  class.  Drift,  sand,  rubble,  boulders, 
come  next ;  and  finally  volcanic  products,  like  lava, 
ashes,  pumice.  He  was  quite  positive  that  all  basalt 
was  of  aqueous  origin  and  of  quite  recent  formation. 
This  part  of  his  teaching  was  soon  challenged.  He 
was  truer  to  his  own  essential  purposes  in  writing  a 
valuable  treatise  on  metalliferous  veins  (Die  Neue 
Theorie  der  Engange),  but  even  there  his  general 


132         THE  HISTORY  OF  SCIENCE 

views  are  apparent,  for  he  holds  that  veins  are  clefts 
filled  in  from  above  by  crystallization  from  aqueous 
solution. 

Before  Werner  had  begun  his  teaching  career  at 
Freiberg,  Desmarest,  the  French  geologist,  had  made 
a  special  study  of  the  basalts  of  Auvergne.  As  a 
mathematician  he  was  able  to  make  a  trigonometrical 
survey  of  that  district,  and  constructed  a  map  show- 
ing the  craters  of  volcanoes  of  different  ages,  the 
streams  of  lava  following  the  river  courses,  and  the 
relation  of  basalt  to  lava,  scoria,  ashes,  and  other 
recognized  products  of  volcanic  action.  In  1788  he 
was  made  inspector-general  of  French  manufactures, 
later  superintendent  of  the  porcelain  works  at  Sevres. 
He  lived  to  the  age  of  ninety,  and  whenever  Neptu- 
nists  would  try  to  draw  him  into  argument,  the  old 
man  would  simply  say,  "  Go  and  see." 

James  Hutton  (1726-1797),  the  illustrious  Scotch 
geologist,  had  something  of  the  same  aversion  to 
speculation  that  did  not  rest  on  evidence ;  though  he 
was  eminently  a  philosopher  in  the  strictest  sense  of 
the  word,  as  his  three  quarto  volumes  on  the  Prin- 
ciples of  Knowledge  bear  witness.  Hutton  was  well 
trained  at  Edinburgh  in  the  High  School  and  Uni- 
versity. In  a  lecture  on  logic  an  illustrative  refer- 
ence to  aqua  regia  turned  his  mind  to  the  study  of 
chemistry.  He  engaged  in  experiments,  and  ulti- 
mately made  a  fortune  by  a  process  for  the  manufac- 
ture of  sal  ammoniac  from  coal-soot.  In  the  mean 
time  he  studied  medicine  at  Edinburgh,  Paris,  and 
Leyden,  and  continued  the  pursuit  of  chemistry. 
Then,  having  inherited  land  in  Berwickshire,  he 
studied  husbandry  in  Norfolk  and  took  interest  in  the 


INTERACTION  OF  THE  SCIENCES    133 

surface  of  the  land  and  water-courses  ;  later  he  pur- 
sued these  studies  in  Flanders.  During  years  of  highly 
successful  farming,  during  which  Hutton  introduced 
new  methods  in  Berwickshire,  he  was  interested  in 
meteorology,  and  in  geology  as  related  to  soils.  In 
1768,  financially  independent,  Dr.  Hutton  retired 
to  reside  in  Edinburgh. 

He  was  very  genial  and  sociable  and  was  in  close 
association  with  Adam  Smith,  the  economist,  and 
with  Black,  known  in  the  history  of  chemistry  in  con- 
nection with  carbonic  acid,  latent  heat,  and  experi- 
ments in  magnesia,  quicklime,  and  other  alkaline  sub- 
stances (1777).  Playfair,  professor  of  mathematics, 
and  later  of  natural  philosophy,  was  Hutton's  disciple 
and  intimate  friend.  In  the  distinguished  company 
of  the  Royal  Society  of  Edinburgh,  established  in 
1782,  the  founder  of  dynamic  geology  was  stimulated 
by  these  and  other  distinguished  men  like  William 
Robertson,  Lord  Kames,  and  Watt.  The  first  volume 
of  the  Transactions  contains  his  Theory  of  Rains, 
and  the  first  statement  of  his  famous  Theory  of  the 
Earth.  He  was  very  broad-minded  and  enthusiastic 
and  would  rejoice  in  Watt's  improvements  of  the 
steam  engine  or  Cook's  discoveries  in  the  South 
Pacific.  Without  emphasizing  his  indebtedness  to 
Horace -Benedict  de  Saussure,  physicist,  geologist, 
meteorologist,  botanist,  who  gave  to  Europeans  an 
appreciation  of  the  sublime  in  nature,  nor  dwelling 
further  on  the  range  of  Button's  studies  in  language, 
general  physics,  etc.,  it  is  already  made  evident  that 
his  mind  was  such  as  to  afford  comprehensiveness 
of  view. 

He  expressed  the  wish  to  induce  men  who  had 


134         THE  HISTORY  OF  SCIENCE 

sufficient  knowledge  of  the  particular  branches  of 
science,  to  employ  their  acquired  talents  in  promoting 
general  science,  or  knowledge  of  the  great  system, 
where  ends  and  means  are  wisely  adjusted  in  the  con- 
stitution of  the  material  universe.  Philosophy,  he 
says,  is  surely  the  ultimate  end  of  human  knowledge, 
or  the  object  at  which  all  sciences  properly  must  aim. 
Sciences  no  doubt  should  promote  the  arts  of  life ; 
but,  he  proceeds,  what  are  all  the  arts  of  life,  or  all 
the  enjoyments  of  mere  animal  nature,  compared  with 
the  art  of  human  happiness,  gained  by  education  and 
brought  to  perfection  by  philosophy  ?  Man  must 
learn  to  know  himself;  he  must  see  his  station 
among  created  things;  he  must  become  a  moral 
agent.  But  it  is  only  by  studying  things  in  general 
that  he  may  arrive  at  this  perfection  of  his  nature. 
"  To  philosophize,  therefore,  without  proper  science, 
is  in  vain  ;  although  it  is  not  vain  to  pursue  science, 
without  proceeding  to  philosophy." 

In  the  early  part  of  1785  Dr.  Hutton  presented 
his  Theory  of  the  Earth  in  ninety-six  pages  of  per- 
fectly lucid  English.  The  globe  is  studied  as  a  ma- 
chine adapted  to  a  certain  end,  namely,  to  provide  a 
habitable  world  for  plants,  for  animals,  and,  above 
all,  for  intellectual  beings  capable  of  the  contempla- 
tion and  the  appreciation  of  order  and  harmony. 
Hutton's  theory  might  be  made  plain  by  drawing  an 
analogy  between  geological  and  meteorological  ac- 
tivities. The  rain  descends  on  the  earth  ;  streams  and 
rivers  bear  it  to  the  sea  ;  the  aqueous  vapors,  drawn 
from  the  sea,  supply  the  clouds,  and  the  circuit  is  com- 
plete. Similarly,  the  soil  is  formed  from  the  over- 
hanging mountains ;  it  is  washed  as  sediment  into  the 


INTERACTION  OF  THE  SCIENCES    135 

sea ;  it  is  elevated,  after  consolidation,  into  the  over- 
hanging mountains.  The  earth  is  more  than  a  mech- 
anism, it  is  an  organism  that  repairs  and  restores 
itself  in  perpetuity.  Thus  Hutton  explained  the  com- 
position, dissolution,  and  restoration  of  land  upon  the 
globe  on  a  general  principle,  even  as  Newton  had 
brought  a  mass  of  details  under  the  single  law  of 
gravitation. 

Again,  as  Newton  had  widened  man's  conception 
of  space,  so  Hutton  (and  Buffon)  enlarged  his  con- 
ception of  time.  For  the  geologist  did  not  under- 
take to  explain  the  origin  of  things ;  he  found  no 
vestige  of  a  beginning,  —  no  prospect  of  an  end; 
and  at  the  same  time  he  conjured  up  no  hypothet- 
ical causes,  no  catastrophes,  or  sudden  convulsions 
of  nature ;  neither  did  he  (like  Werner)  believe  that 
phenomena  now  present,  were  once  absent ;  but  he 
undertook  to  explain  all  geological  change  by  proc- 
esses in  action  now  as  heretofore.  Countless  ages 
were  requisite  to  form  the  soil  of  our  smiling  val- 
leys, but  "  Time,  which  measures  everything  in  our 
idea,  and  is  often  deficient  to  our  schemes,  is  to  na- 
ture endless  and  as  nothing."  The  calcareous  remains 
of  marine  animals  in  the  solid  body  of  the  earth  bear 
witness  of  a  period  to  which  no  other  species  of 
chronology  is  able  to  remount. 

Hutton's  imagination,  on  the  basis  of  what  can  be 
observed  to-day,  pictured  the  chemical  and  mechan- 
ical disintegration  of  the  rocks ;  and  saw  ice-streams 
bearing  huge  granite  boulders  from  the  declivities  of 
primitive  and  more  gigantic  Alps.  He  believed  (as 
Desmarest)  that  rivulets  and  rivers  have  constructed, 
and  are  constructing,  their  own  valley  systems,  and 


136         THE  HISTORY  OF  SCIENCE 

that  the  denudation  ever  in  progress  would  be  event- 
ually fatal  to  the  sustenance  of  plant  and  animal  and 
man,  if  the  earth  were  not  a  renewable  organism,  in 
which  repair  is  correlative  with  waste. 

All  strata  are  sedimentary,  consolidated  at  the 
bottom  of  the  sea  by  the  pressure  of  the  water  and 
by  subterranean  heat.  How  are  strata  raised  from 
the  ocean  bed  ?  By  the  same  subterranean  force  that 
helped  consolidate  them.  The  power  of  heat  for  the 
expansion  of  bodies,  is,  says  Hutton  (possibly  hav- 
ing in  mind  the  steam  engine),  so  far  as  we  know, 
unlimited.  We  see  liquid  stone  pouring  from  the 
crater  of  a  lofty  volcano  and  casting  huge  rocks  into 
mid-air,  and  yet  find  it  difficult  to  believe  that  Vesu- 
vius and  Etna  themselves  have  been  formed  by  vol- 
canic action.  The  interior  of  the  planet  may  be  a 
fluid  mass,  melted,  but  unchanged  by  the  action  of 
heat.  The  volcanoes  are  spiracles  or  safety-valves, 
and  are  widely  distributed  on  the  surface  of  the 
earth. 

Hutton  believed  that  basalt,  and  the  whinstones 
generally,  are  of  igneous  origin.  Moreover,  he  put 
granite  in  the  same  category,  and  believed  it  had 
been  injected,  as  also  metalliferous  veins,  in  liquid 
state  into  the  stratified  rocks.  If  his  supposition 
were  correct,  then  granite  would  be  found  sending 
out  veins  from  its  large  masses  to  pierce  the  strati- 
fied rocks  and  to  crop  out  where  stratum  meets  stra- 
tum. His  conjecture  was  corroborated  at  Glen  Tilt 
(and  in  the  island  of  Arran).  Hutton  was  so  elated 
at  the  verification  of  his  view  that  the  Scotch  guides 
thought  he  had  struck  gold,  or  silver  at  the  very 
least.  In  the  bed  of  the  river  Tilt  he  could  see  at 


INTERACTION  OF  THE  SCIENCES    137 

six  points  within  half  a  mile  powerful  veins  of  red 
granite  piercing  the  black  micaceous  schist  and  giv- 
ing every  indication  of  having  been  intruded  from 
beneath,  with  great  violence,  into  the  earlier  forma- 
tion. 

Hutton  felt  confirmed  in  his  view  that  in  nature 
there  is  wisdom,  system,  and  consistency.  Even  the 
volcano  and  earthquake,  instead  of  being  accidents, 
or  arbitrary  manifestations  of  divine  wrath,  are  part 
of  the  economy  of  nature,  and  the  best  clue  we  have 
to  the  stupendous  force  necessary  to  heave  up  the 
strata,  inject  veins  of  metals  and  igneous  rocks,  and 
insure  a  succession  of  habitable  worlds. 

In  1795  Dr.  Hutton  published  a  more  elaborate 
statement  of  his  theory  in  two  volumes.  In  1802 
Playfair  printed  Illustrations  of  the  Huttonian 
Theory,  a  simplification,  having,  naturally,  little 
originality.  Before  his  death  In  1797  Hutton  de- 
voted his  time  to  reading  new  volumes  by  Saussure 
on  the  Alps,  and  to  preparing  a  book  on  The  Ele- 
ments of  Agriculture. 

Sir  James  Hall  of  Dunglass  was  a  reluctant  con- 
vert to  Hutton's  system  of  geology.  Three  arguments 
against  the  Huttonian  hypothesis  gave  him  cause  for 
doubt.  Would  not  matter  solidifying  after  fusion 
form  a  glass,  a  vitreous,  rather  than  a  crystalline 
product  ?  Why  do  basalts,  whinstones,  and  other  sup- 
posedly volcanic  rocks  differ  so  much  in  structure 
from  lava?  How  can  marble  and  other  limestones 
have  been  fused,  seeing  that  they  are  readily  cal- 
cined by  heat  ?  Hutton  thought  that  the  compression 
under  which  the  subterranean  heat  had  been  applied 
was  a  factor  in  the  solution  of  these  problems.  He 


138         THE  HISTORY  OF  SCIENCE 

was  encouraged  in  this  view  by  Black,  who,  as  al- 
ready implied,  had  made  a  special  study  of  limestone 
and  had  demonstrated  that  lime  acquires  its  caus- 
ticity through  the  expulsion  of  carbonic  acid. 

Hall  conjectured  in  addition  that  the  rate  at  which 
the  fused  mass  cooled  might  have  some  bearing  on 
the  structure  of  igneous  rocks.  An  accident  in  the 
Leith  glass  works  strengthened  the  probability  of 
his  conjecture  and  encouraged  him  to  experiment. 
A  pot  of  green  bottle-glass  had  been  allowed  to  cool 
slowly  with  the  result  that  it  had  a  stony,  rather  a 
vitreous  structure.  Hall  experimenting  with  glass 
could  secure  either  structure  at  will  by  cooling  rap- 
idly or  slowly,  and  that  with  the  same  specimen. 

He  later  enclosed  some  fragments  of  whin  stone  in 
a  black-lead  crucible  and  subjected  it  to  intense  heat 
in  the  reverberating  furnace  of  an  iron  foundry. 
(He  was  in  consultation  with  Mr.  Wedgwood  on  the 
scale  of  heat,  and  with  Dr.  Hope  and  Dr.  Kennedy, 
chemists.)  After  boiling,  and  then  cooling  rapidly, 
the  contents  of  the  crucible  proved  a  black  glass. 
Hall  repeated  the  experiment,  and  cooled  more  slowly. 
The  result  was  an  intermediate  substance,  neither 
glass  nor  whinstone  —  a  sort  of  slag.  Again  he  heated 
the  crucible  in  the  furnace,  and  removed  quickly  to 
an  open  fire,  which  was  maintained  some  hours  and 
then  permitted  to  die  out.  The  result  in  this  case 
was  a  perfect  whinstone.  Similar  results  were  ob- 
tained with  regular  basalts  and  different  specimens 
of  igneous  rock. 

Hall  next  experimented  with  lava  from  Vesuvius, 
Etna,  Iceland,  and  elsewhere,  and  found  that  it  be- 
haved like  whinstone.  Dr.  Kennedy  by  careful  chem- 


INTERACTION  OF  THE  SCIENCES    139 

ical  analysis  confirmed  Hall's  judgment  of  the  simi- 
larity of  these  two  igneous  products. 

Still  later  Hall  introduced  chalk  and  powdered 
limestone  into  porcelain  tubes,  gun  barrels,  and  tubes 
bored  in  solid  iron,  which  he  sealed  and  brought  to 
very  high  temperatures.  He  obtained,  by  fusion,  a 
crystalline  carbonate  resembling  marble.  Under  the 
high  pressure  in  the  tube  the  carbonic  acid  was  re- 
tained. By  these  and  other  experiments  this  doubt- 
ing disciple  confirmed  Hutton's  theory,  and  became 
one  of  the  great  founders  of  experimental  geology. 

It  remained  for  William  Smith  (1769-1839), 
surveyor  and  engineer,  to  develop  that  species  of 
chronology  that  Hutton  had  ascribed  to  organic  re- 
mains in  the  solid  strata,  to  arrange  these  strata  in 
the  order  of  time,  and  thus  to  become  the  founder  of 
historic  geology.  For  this  task  his  early  education 
might  at  first  glance  seem  inadequate.  His  only 
schooling  was  received  in  an  elementary  institution 
in  Oxfordshire.  He  managed,  however,  to  acquire 
some  knowledge  of  geometry,  and  at  eighteen  entered, 
as  assistant,  a  surveyor's  office.  He  never  attained 
any  literary  facility,  and  was  always  more  success- 
ful in  conveying  his  observations  by  maps,  drawings, 
and  conversation  than  by  books. 

However,  he  early  began  his  collection  of  minerals 
and  observed  the  relation  of  the  soil  and  the  vegeta- 
tion to  the  underlying  rocks.  Engaged  at  the  age  of 
twenty-four  in  taking  levelings  for  a  canal,  he  no- 
ticed that  the  strata  were  not  exactly  horizontal,  but 
dipped  to  the  east  "  like  slices  of  bread  and  butter," 
a  phenomenon  he  considered  of  scientific  significance. 
In  connection  with  his  calling  he  had  an  opportunity 


140         THE  HISTORY  OF  SCIENCE 

of  traveling  to  the  north  of  England  and  so  extended 
the  range  of  his  observation,  always  exceptionally 
alert.  For  six  years  he  was  engaged,  as  engineer,  in 
the  construction  of  the  Somerset  Coal  Canal,  where 
he  enlarged  and  turned  to  practical  account  his 
knowledge  of  strata. 

Collectors  of  fossils  (as  Lamarck  afterwards  called 
organic  remains)  were  surprised  to  find  Smith  able 
to  tell  in  what  formation  their  different  specimens 
had  been  found,  and  still  more  when  he  enunciated 
the  view  that  "  whatever  strata  were  to  be  found 
in  any  part  of  England  the  same  remains  would  be 
found  in  it  and  no  other."  Moreover,  the  same  order 
of  superposition  was  constant  among  the  strata,  as 
Werner,  of  whom  Smith  knew  nothing,  had  indeed 
taught.  Smith  was  able  to  dictate  a  Tabular  View 
of  British  Strata  from  coal  to  chalk  with  the  char- 
acteristic fossils,  establishing  an  order  that  was  found 
to  obtain  on  the  Continent  of  Europe  as  well  as  in 
Britain. 

He  constructed  geological  maps  of  Somerset  and 
fourteen  other  English  counties,  to  which  the  atten- 
tion of  the  Board  of  Agriculture  was  called.  They 
showed  the  surface  outcrops  of  strata,  and  were  in- 
tended to  be  of  assistance  in  mining,  roadmaking, 
canal  construction,  draining,  and  water  supply.  It 
was  at  the  time  of  William  Smith's  scientific  dis- 
coveries that  the  public  interest  in  canal  transporta- 
tion was  at  its  height  in  England,  and  his  study  of 
the  strata  was  a  direct  outcome  of  his  professional 
activity.  He  called  himself  a  mineral  surveyor,  and 
he  traveled  many  thousand  miles  yearly  in  connec- 
tion with  his  calling  and  his  interest  in  the  study  of 


INTERACTION  OF  THE  SCIENCES    141 

geology.  In  1815  he  completed  an  extensive  geolog- 
ical map  of  England,  on  which  all  subsequent  geo- 
logical maps  have  been  modeled.  It  took  into  account 
the  collieries,  mines,  canals,  marshes,  fens,  and  the 
varieties  of  soil  in  relation  to  the  substrata. 

Later  (1816-1819)  Smith  published  four  vol- 
umes, Strata  Identified  by  Organized  Fossils, 
which  put  on  record  some  of  his  extensive  observa- 
tions. His  mind  was  practical  and  little  given  to 
speculation.  It  does  not  lie  in  our  province  here  to 
trace  his  influence  on  Cuvier  and  other  scientists, 
but  to  add  his  name  as  a  surveyor  and  engineer  to 
the  representatives  of  mineralogy,  chemistry,  physics, 
mathematics,  philosophy,  and  various  industries  and 
vocations,  which  contributed  to  the  early  develop- 
ment of  modern  geology. 

REFERENCES 

Sir  A.  Geikie,  Founders  of  Geology. 

James  Hutton,  Theory  of  the  Earth. 

Sir  Charles  Lyell,  Principles  of  Geology. 

John  Playfair,  Illustrations  of  the  Huttonian  Theory. 

K.  A.  v.  Zittel,  History  of  Geology  and  Palaeontology. 


CHAPTER  XI 

SCIENCE  AND    RELIGION —  KANT,  LAMBERT, 
LAPLACE,    SIR    WILLIAM    HERSCHEL 

HUTTON  had  advanced  the  study  of  geology  by 
concentrating  attention  on  the  observable  phenomena 
of  the  earth's  crust,  and  turning  away  from  specula- 
tions about  the  origin  of  the  world  and  the  relation 
of  this  sphere  to  other  units  of  the  cosmos.  In  the 
same  century,  however,  other  scientists  and  phi- 
losophers were  attracted  by  these  very  problems 
which  seemed  not  to  promise  immediate  or  demon- 
strative solution,  and  through  their  studies  they  ar- 
rived at  conclusions  which  profoundly  affected  the 
science,  the  ethics,  and  the  religion  of  the  civilized 
world. 

Whether  religion  be  defined  as  a  complex  feeling 
of  elation  and  humility  —  a  sacred  fear  —  akin  to 
the  aesthetic  sense  of  the  sublime;  or,  as  an  intel- 
lectual recognition  of  some  high  powers  which  gov- 
ern us  below  —  of  some  author  of  all  things,  of  some 
force  social  or  cosmic  which  tends  to  righteousness  ; 
or,  as  the  outcrop  of  the  moral  life  touched  with 
light  and  radiant  with  enthusiasm ;  or,  as  partaking 
of  the  nature  of  all  these  :  it  cannot  be  denied  that 
the  eighteenth  century  contributed  to  its  clarifica- 
tion and  formulation,  especially  through  the  efforts 
of  the  German  philosopher,  Immanuel  Kant  (1724- 
1804).  Yet  it  is  not  difficult  to  show  that  the 
philosophy  of  Kant  and  of  those  associated  with 


SCIENCE  AND  RELIGION  143 

him  was  greatly  influenced  by  the  science  of  the 
time,  and  that,  in  fact,  in  his  early  life  he  was  a 
scientist  rather  than  a  philosopher  in  the  stricter 
sense.  His  General  Natural  History  and  Theory 
of  the  Heavens,  written  at  the  age  of  thirty-one, 
enables  us  to  follow  his  transition  from  science  to 
philosophy,  and,  more  especially,  to  trace  the  influ- 
ence of  his  theory  of  the  origin  of  the  heavenly 
bodies  on  his  religious  conceptions. 

For  part  of  this  theory  Kant  was  indebted  to 
Thomas  Wright  of  Durham  (1711-1786).  Wright 
was  the  son  of  a  carpenter,  became  apprenticed  to  a 
watchmaker,  went  to  sea,  later  became  an  engraver, 
a  maker  of  mathematical  instruments,  rose  to  afflu- 
ence, wrote  a  book  on  navigation,  and  was  offered  a 
professorship  of  navigation  in  the  Imperial  Academy 
of  St.  Petersburg.  It  was  in  1750  that  he  pub- 
lished, in  the  form  of  nine  letters,  the  work  that 
stimulated  the  mind  of  Kant,  An  Original  Theory 
or  New  Hypothesis  of  the  Universe.  The  author 
thought  that  the  revelation  of  the  structure  of  the 
heavens  naturally  tended  to  propagate  the  principles 
of  virtue  and  vindicate  the  laws  of  Providence.  He 
regarded  the  universe  as  an  infinity  of  worlds  acted 
upon  by  an  eternal  Agent,  and  full  of  beings,  tend- 
ing through  their  various  states  to  a  final  perfection. 
Who,  conscious  of  this  system,  can  avoid  being  filled 
with  a  kind  of  enthusiastic  ambition  to  contribute 
his  atom  toward  the  due  admiration  of  its  great  and 
Divine  Author? 

Wright  discussed  the  nature  of  mathematical  cer- 
tainty and  the  various  degrees  of  moral  probability 
proper  for  conjecture  (thus  pointing  to  a  distinction 


144         THE  HISTORY  OF  SCIENCE 

that  ultimately  became  basal  in  the  philosophy  of 
Kant).  When  he  claimed  that  the  sun  is  a  vast 
body  of  blazing  matter,  and  that  the  most  distant 
star  is  also  a  sun  surrounded  by  a  system  of  planets, 
he  knew  that  he  was  reasoning  by  analogy  and  not 
enunciating  what  is  immediately  demonstrable.  Yet 
this  multitude  of  worlds  opens  out  to  us  an  immense 
field  of  probation  and  an  endless  scene  of  hope  to 
ground  our  expectation  of  an  ever  future  happiness 
upon,  suitable  to  the  native  dignity  of  the  awful 
Mind  which  made  and  comprehended  it. 

The  most  striking  part  of  Wright's  Original  Theory 
relates  to  the  construction  of  the  Milky  Way,  which 
he  thought  analogous  in  form  to  the  rings  of  Saturn. 
From  the  center  the  arrangement  of  the  systems  and 
the  harmony  of  the  movements  could  be  discerned, 
but  our  solar  system  occupies  a  section  of  the  belt, 
and  what  we  see  of  the  creation  gives  but  a  confused 
picture,  unless  by  an  effort  of  imagination  we  attain 
the  right  point  of  view.  The  various  cloudy  stars  or 
light  appearances  are  nothing  but  a  dense  accumu- 
lation of  stars.  What  less  than  infinity  can  circum- 
scribe them,  less  than  eternity  comprehend  them,  or 
less  than  Omnipotence  produce  or  support  them? 
He  passes  on  to  a  discussion  of  time  and  space  with 
regard  to  the  known  objects  of  immensity  and  dura- 
tion, and  in  the  ninth  letter  says  that,  granting  the 
creation  to  be  circular  or  orbicular,  we  can  suppose 
in  the  center  of  the  whole  an  intelligent  principle, 
the  to-all-extending  eye  of  Providence,  or,  if  the 
creation  is  real,  and  not  merely  ideal,  a  sphere  of 
some  sort.  Around  this  the  suns  keep  their  orbits 
harmoniously,  all  apparent  irregularities  arising  from 


SCIENCE  AND  RELIGION  145 

our  eccentric  view.   Moreover,  space  is  sufficient  for 
many  such  systems. 

Kant  resembled  his  predecessor  in  his  recognition 
of  the  bearing  on  moral  and  religious  conceptions 
of  the  study  of  the  heavens  and  also  in  his  treat- 
ment of  many  astronomical  details,  sometimes  merely 
adopting,  more  frequently  developing  or  modifying, 
the  teachings  of  Wright.  He  held  that  the  stars 
constitute  a  system  just  as  much  as  do  the  planets  of 
our  solar  system,  and  that  other  solar  systems  and  other 
Milky  Ways  may  have  been  produced  in  the  bound- 
less fields  of  space.  Indeed,  he  is  inclined  to  identify 
with  the  latter  systems  the  small  luminous  elliptical 
areas  in  the  heavens  reported  by  Maupertuis  in  1742. 
Kant  also  accepted  Wright's  conjecture  of  a  central 
sun  or  globe  and  even  made  selection  of  one  of  the 
stars  to  serve  in  that  office,  and  taught  that  the  stars 
consist  like  our  sun  of  a  fiery  mass.  One  cannot 
contemplate  the  world-structure  without  recognizing 
the  excellent  orderliness  of  its  arrangement,  and 
perceiving  the  sure  indications  of  the  hand  of  God 
in  the  completeness  of  its  relations.  Reason,  he  says 
in  iheAllgemeineNaturgeschichte,  refuses  to  believe 
it  the  work  of  chance.  It  must  have  been  planned  by 
supreme  wisdom  and  carried  into  effect  by  Omnipo- 
tence. 

Kant  was  especially  stimulated  by  the  analogy  be- 
tween the  Milky  Way  and  the  rings  of  Saturn.  He  did 
not  agree  with  Wright  that  they,  or  the  cloudy  areas, 
would  prove  to  be  stars  or  small  satellites,  but  rather 
that  both  consisted  of  vapor  particles.  Giving  full 
scope  to  his  imagination,  he  asks  if  the  earth  as  well 
as  Saturn  may  not  have  been  surrounded  by  a  ring. 


146         THE  HISTORY  OF  SCIENCE 

Might  not  this  ring  explain  the  supercelestial  waters 
that  gave  such  cause  for  ingenuity  to  the  medieval 
writers?  Not  only  so,  but,  had  such  a  vaporous  ring 
broken  and  been  precipitated  to  the  earth,  it  would 
have  caused  a  prolonged  Deluge,  and  the  subsequent 
rainbow  in  the  heavens  might  very  well  have  been 
interpreted  as  an  allusion  to  the  vanished  ring,  and 
as  a  promise.  This,  however,  is  not  Kant's  charac- 
teristic manner  in  supporting  moral  and  religious 
truth. 

To  account  for  the  origin  of  the  solar  system,  the 
German  philosopher  assumes  that  at  the  beginning 
of  all  things  the  material  of  which  the  sun,  planets, 
satellites,  and  comets  consist,  was  uncompounded,  in 
its  primary  elements,  and  filled  the  whole  space  in 
which  the  bodies  formed  out  of  it  now  revolve.  This 
state  of  nature  seemed  to  be  the  very  simplest  that 
could  follow  upon  nothing.  In  a  space  filled  in  this 
way  a  state  of  rest  could  not  last  for  more  than  a 
moment.  The  elements  of  a  denser  kind  would,  ac- 
cording to  the  law  of  gravitation,  attract  matter  of 
less  specific  gravity.  Repulsion,  as  well  as  attraction, 
plays  a  part  among  the  particles  of  matter  dissemi- 
nated in  space.  Through  it  the  direct  fall  of  particles 
may  be  diverted  into  a  circular  movement  about  the 
center  toward  which  they  are  gravitating. 

Of  course,  in  our  system  the  center  of  attraction 
is  the  nucleus  of  the  sun.  The  mass  of  this  body  in- 
creases rapidly,  as  also  its  power  of  attraction.  Of 
the  particles  gravitating  to  it  the  heavier  become 
heaped  up  in  the  center.  In  falling  from  different 
heights  toward  this  common  focus  the  particles  can- 
not have  such  perfect  equality  of  resistance  that  no 


SCIENCE  AND  RELIGION  147 

lateral  movements  should  be  set  up.  A  general  circu- 
latory motion  is  in  fact  established  ultimately  in  one 
direction  about  the  central  mass,  which  receiving  new 
particles  from  the  encircling  current  rotates  in  har- 
mony with  it. 

Mutual  interference  in  the  particles  outside  the 
mass  of  the  sun  prevents  all  accumulation  except  in 
one  plane  and  that  takes  the  form  of  a  thin  disk  con- 
tinuous with  the  sun's  equator.  In  this  circulating 
vaporous  disk  about  the  sun  differences  of  density 
give  rise  to  zones  not  unlike  the  rings  of  Saturn. 
These  zones  ultimately  contract  to  form  planets,  and 
as  the  planets  are  thrown  off  from  the  central  solar 
mass  till  an  equilibrium  is  established  between  the 
centripetal  and  centrifugal  forces,  so  the  satellites  in 
turn  are  formed  from  the  planets.  The  comets  are  to 
be  regarded  as  parts  of  the  system,  akin  to  the  planets, 
but  more  remote  from  the  control  of  the  centripetal 
force  of  the  sun.  It  is  thus  that  Kant  conceived  the 
nebular  hypothesis,  accounting  (through  the  forma- 
tion of  the  heavenly  bodies  from  a  cloudy  vapor  simi- 
lar to  that  still  observable  through  the  telescope)  for 
the  revolution  of  the  planets  in  one  direction  about 
the  sun ;  the  rotation  of  sun  and  planets ;  the  revo- 
lution and  rotation  of  satellites;  the  comparative 
densities  of  the  heavenly  bodies ;  the  materials  in  the 
tails  of  comets ;  the  rings  of  Saturn,  and  other  celes- 
tial phenomena.  Newton,  finding  no  matter  between 
the  planets  to  maintain  the  community  of  their  move- 
ments, asserted  that  the  immediate  hand  of  God  had 
instituted  the  arrangement  without  the  intervention 
of  the  forces  of  Nature.  His  disciple  Kant  now  under- 
took to  explain  an  additional  number  of  phenomena 


148         THE  HISTORY  OF  SCIENCE 

on  mechanical  principles.  Granted  the  existence  of 
matter,  he  felt  capable  of  tracing  the  cosmic  evolu- 
tion, but  at  the  same  time  he  maintained  and  strength- 
ened his  religious  position,  and  did  not  assume  (like 
Democritus  and  Epicurus)  eternal  motion  without  a 
Creator  or  the  coming  together  of  atoms  by  accident 
or  haphazard. 

It  might  be  objected,  he  says,  that  Nature  is  suffi- 
cient unto  itself;  but  universal  laws  of  the  action  of 
matter  serve  the  plan  of  the  Supreme  Wisdom.  There 
is  convincing  proof  of  the  existence  of  God  in  the 
very  fact  that  Nature,  even  in  chaos,  cannot  proceed 
otherwise  than  regularly  and  according  to  law.  Even 
in  the  essential  properties  of  the  elements  that  consti- 
tuted the  chaos,  there  could  be  traced  the  mark  of 
that  perfection  which  they  have  derived  from  their 
origin,  their  essential  character  being  a  consequence 
of  the  eternal  idea  of  the  Divine  Intelligence.  Mat- 
ter, which  appears  to  be  merely  passive  and  wanting 
in  form  and  arrangement,  has  in  its  simplest  state  a 
tendency  to  fashion  itself  by  a  natural  development 
into  a  more  perfect  constitution.  Matter  must  be  con- 
sidered as  created  by  God  in  accordance  with  law  and 
as  ever  obedient  to  law,  not  as  an  independent  or  hos- 
tile force  needing  occasional  correction.  To  suppose 
the  material  world  not  under  law  would  be  to  believe 
in  a  blind  fate  rather  than  in  Providence.  It  is  Nature's 
harmony  and  order  revealed  to  our  understanding  that 
give  us  a  clue  to  its  creation  by  an  understanding  of 
the  highest  order. 

In  a  work  written  eight  years  later  Kant  sought  to 
furnish  people  of  ordinary  intelligence  with  a  proof 
of  the  existence  of  God.  It  might  seem  irrelevant  in 


SCIENCE  AND  RELIGION  149 

such  a  production  to  give  an  exposition  of  physical 
phenomena,  but,  intent  on  his  method  of  mounting  to 
a  knowledge  of  God  by  means  of  natural  science,  he 
here  repeats  in  summarized  form  his  theory  of  the 
origin  of  the  heavenly  bodies.  Moreover,  the  in- 
fluence of  his  astronomical  studies  persisted  in  his 
maturest  philosophy,  as  can  be  seen  in  the  well-known 
passage  at  the  conclusion  of  his  ethical  work,  the 
Critique  of  the  Practical  Reason  (1788)  :  "There 
are  two  things  that  fill  my  spirit  with  ever  new  and 
increasing  awe  and  reverence  —  the  more  frequently 
and  the  more  intently  I  contemplate  them  —  the  star- 
strewn  sky  above  me  and  the  moral  law  within."  His 
religious  and  ethical  conceptions  were  closely  asso- 
ciated with  —  indeed,  dependent  upon — an  orderly 
and  infinite  physical  universe. 

In  the  mathematician,  astronomer,  physicist,  and 
philosopher,  J.  H.  Lambert  (1728-1777),  Kant 
found  a  genius  akin  to  his  own,  and  through  him 
hoped  for  a  reformation  of  philosophy  on  the  basis 
of  the  study  of  science.  Lambert  like  his  contempo- 
rary was  a  disciple  of  Newton,  and  in  1761  he  pub- 
lished a  book  in  the  form  of  letters  expressing  views 
in  reference  to  the  Milky  Way,  fixed  stars,  central 
sun,  very  similar  to  those  published  by  Kant  in 
1755.  Lambert  had  heard  of  Wright's  work,  so 
similar  to  his  own,  a  year  after  the  latter  was  written. 

Comets,  now  robbed  of  many  of  the  terrors  with 
which  ancient  superstition  endowed  them,  might,  he 
says,  seem  to  threaten  catastrophe,  by  colliding  with 
the  planets  or  by  carrying  off  a  satellite.  But  the 
same  hand  which  has  cast  the  celestial  spheres  in 
space,  has  traced  their  course  in  the  heavens,  and 


150         THE  HISTORY  OF  SCIENCE 

does  not  allow  them  to  wander  at  random  to  distuib 
and  destroy  each  other.  Lambert  imagines  that  all 
these  bodies  have  exactly  the  volume,  weight,  posi- 
tion, direction,  and  speed  necessary  for  the  avoidance 
of  collisions.  If  we  confess  a  Supreme  Ruler  who 
brought  order  from  chaos,  and  gave  form  to  the  uni- 
verse ;  it  follows  that  this  universe  is  a  perfect  work, 
the  impress,  picture,  reflex  of  its  Creator's  perfec- 
tion. Nothing  is  left  to  blind  chance.  Means  are 
fitted  to  ends.  There  is  order  throughout,  and  in 
this  order  the  dust  beneath  our  feet,  the  stars  above 
our  heads,  atoms  and  worlds,  are  alike  compre- 
hended. 

Laplace  in  his  statement  of  the  nebular  hypothe- 
sis made  no  mention  of  Kant.  He  sets  forth,  in  the 
Exposition  of  the  Solar  System,  the  astronomical 
data  that  the  theory  is  designed  to  explain :  the 
movements  of  the  planets  in  the  same  direction  and 
almost  in  the  same  plane ;  the  movements  of  the  sat- 
ellites in  the  same  direction  as  those  of  the  planets ; 
the  rotation  of  these  different  bodies  and  of  the  sun 
in  the  same  direction  as  their  projection,  and  in 
planes  little  different ;  the  small  eccentricity  of  the 
orbits  of  planets  and  satellites  ;  the  great  eccentricity 
of  the  orbits  of  comets.  How  on  the  ground  of  these 
data  are  we  to  arrive  at  the  cause  of  the  earliest 
movements  of  the  planetary  system  ? 

A  fluid  of  immense  extent  must  be  assumed,  em- 
bracing all  these  bodies.  It  must  have  circulated 
about  the  sun  like  an  atmosphere  and,  in  virtue  of 
the  excessive  heat  which  was  engendered,  it  may  be 
assumed  that  this  atmosphere  originally  extended 
beyond  the  orbits  of  all  the  planets,  and  was  con- 


SCIENCE   AND   RELIGION  151 

tracted  by  stages  to  its  present  form.  In  its  primi- 
tive state  the  sun  resembled  the  nebulae,  which  are 
to  be  observed  through  the  telescope,  with  fiery  cen- 
ters and  cloudy  periphery.  One  can  imagine  a  more 
and  more  diffuse  state  of  the  nebulous  matter. 

Planets  were  formed,  in  the  plane  of  the  equator 
and  at  the  successive  limits  of  the  nebulous  atmos- 
phere, by  the  condensation  of  the  different  zones 
which  it  abandoned  as  it  cooled  and  contracted.  The 
force  of  gravity  and  the  centrifugal  force  sufficed  to 
maintain  in  its  orbit  each  successive  planet.  From  the 
cooling  and  contracting  masses  that  were  to  consti- 
tute the  planets  smaller  zones  and  rings  were  formed. 
In  the  case  of  Saturn  there  was  such  regularity  in 
the  rings  that  the  annular  form  was  maintained ;  as 
a  rule  from  the  zones  abandoned  by  the  planet-mass 
satellites  resulted.  Differences  of  temperature  and 
density  of  the  parts  of  the  original  mass  account  for 
the  eccentricity  of  orbits,  and  deviations  from  the 
plane  of  the  equator. 

In  his  Celestial  Mechanics  (1825)  Laplace  states 
that,  according  to  HerscheFs  observations,  Saturn's 
rotation  is  slightly  quicker  than  that  of  its  rings. 
This  seemed  a  confirmation  of  the  hypothesis  of  the 
Exposition  du  SysCeme  du  Monde. 

When  Laplace  presented  the  first  edition  of  this 
earlier  work  to  Napoleon,  the  First  Consul  said  : 
"  Newton  has  spoken  of  God  in  his  book.  I  have 
already  gone  through  yours,  and  I  have  not  found 
that  name  in  it  a  single  time."  To  this  Laplace  is 
said  to  have  replied :  "  First  Citizen  Consul,  I  have 
not  had  need  of  that  hypothesis."  The  astronomer 
did  not,  however,  profess  atheism ;  like  Kant  he  felt 


152         THE  HISTORY  OF  SCIENCE 

competent  to  explain  on  mechanical  principles  the 
development  of  the  solar  system  from  the  point  at 
which  he  undertook  it.  In  his  later  years  he  desired 
that  the  misleading  anecdote  should  be  suppressed. 
So  far  was  he  from  self-sufficiency  and  dogmatism 
that  his  last  utterance  proclaimed  the  limitations  of 
even  the  greatest  intellects :  "  What  we  know  is  little 
enough,  what  we  don't  know  is  immense"  (Ce  que 
nous  connaissons  est  pen  de  chose,  ce  que  nous  ig- 
norons  est  immense). 

Sir  William  Herschel's  observations,  extended 
over  many  years,  confirmed  both  the  nebular  hypoth- 
esis and  the  theory  of  the  systematic  arrangement  of 
the  stars.  He  made  use  of  telescopes  20  and  40  feet 
in  focal  length,  and  of  18.7  and  48  inches  aperture, 
and  was  thereby  enabled,  as  Humboldt  said,  to  sink 
a  plummet  amid  the  fixed  stars,  or,  in  his  own 
phrase,  to  gauge  the  heavens.  The  Construction  of 
the  Heavens  was  always  the  ultimate  object  of  his 
observations.  In  a  contribution  on  this  subject  sub- 
mitted to  the  Royal  Society  in  1787  he  announced 
the  discovery  of  466  new  nebula  and  clusters  of 
stars.  The  sidereal  heavens  are  not  to  be  regarded 
as  the  concave  surface  of  a  sphere,  from  the  center 
of  which  the  observer  might  be  supposed  to  look, 
but  rather  as  resembling  a  rich  extent  of  ground 
or  chains  of  mountains  in  which  the  geologist  dis- 
covers many  strata  consisting  of  various  materials. 
The  Milky  Way  is  one  stratum  and  in  it  our  sun 
is  placed,  though  perhaps  not  in  the  very  center  of 
its  thickness. 

By  1811  he  had  greatly  increased  his  observations 
of  the  nebulae  and  could  arrange  them  in  series  differ- 


SCIENCE   AND   RELIGION  153 

iug  in  extent,  condensation,  brightness,  general  form, 
possession  of  nuclei,  situation,  and  in  resemblance  to 
comets  and  to  stars.  They  ranged  from  a  faint  trace 
of  extensive  diffuse  nebulosity  to  a  nebulous  star  with 
a  mere  vestige  of  cloudiness.  Herschel  was  able  to 
make  the  series  so  complete  that  the  difference  be- 
tween the  members  was  no  more  than  could  be  found 
in  a  series  of  pictures  of  the  human  figure  taken  from 
the  birth  of  a  child  till  he  comes  to  be  a  man  in  his 
prime.  The  difference  between  the  diffuse  nebulous 
matter  and  the  star  is  so  striking  that  the  idea  of 
conversion  from  one  to  the  other  would  hardly  occur 
to  any  one  without  evidence  of  the  intermediate 
steps.  It  is  highly  probable  that  each  successive 
state  is  the  result  of  the  action  of  gravity. 

In  his  last  statement,  1818,  he  admitted  that  to  his 
telescopes  the  Milky  Way  had  proved  fathomless, 
but  on  "  either  side  of  this  assemblage  of  stars,  pre- 
sumably in  ceaseless  motion  round  their  common 
center  of  gravity,  Herschel  discovered  a  canopy  of 
discrete  nebulous  masses,  such  as  those  from  the  con- 
densation of  which  he  supposed  the  whole  stellar 
universe  to  be  formed." 

In  the  theory  of  the  evolution  of  the  heavenly  bodies, 
as  set  forth  by  Kant,  Laplace,  and  Herschel,  it  was 
assumed  that  the  elements  that  composed  the  earth 
are  also  to  be  found  elsewhere  throughout  the  solar 
system  and  the  universe.  The  validity  of  this  assump- 
tion was  finally  established  by  spectrum  analysis.  But 
this  vindication  was  in  part  anticipated,  at  the  begin- 
ning of  the  nineteenth  century,  by  the  analysis  of 
meteorites.  In  these  were  found  large  quantities  of 
iron,  considerable  percentages  of  nickel,  as  well  as 


154         THE  HISTORY  OF  SCIENCE 

cobalt,  copper,  silicon,  phosphorus,  carbon,  magne- 
sium, zinc,  and  manganese. 

REFERENCES 

G.  F.  Becker,  Kant  as  a  Natural  Philosopher,  American  Jour- 
nal of  Science,  vol.  v  (1898),  pp.  97-112. 

W.  W.  Bryant,  A  History  of  Astronomy. 

Agnes  M.  Clerke,  History  of  Astronomy  during  the  Nineteenth 
Century. 

Agnes  M.  Clerke,  The  Herschels  and  Modern  Astronomy. 

Sir  William  Herschel,  Papers  on  the  Construction  of  the 
Heavens  (Philosophical  Transactions,  1784,  1811,  etc.). 

A.  R.  Hinks,  Astronomy  (Home  University  Library). 

E.  W.  Maunders,  The  Science  of  the  Stars  (The  People's  Books). 


CHAPTER  XII 

THE  REIGN  OF  LAW DALTON,  JOULE 

IN  the  middle  of  the  eighteenth  century,  when 
Lambert  and  Kant  were  recognizing  system  and 
design  in  the  heavens,  little  progress  had  been 
made  toward  discovering  the  constitution  of  matter 
or  revealing  the  laws  of  the  hidden  motions  of 
things.  Boyle  had,  indeed,  made  a  beginning,  not 
only  by  his  study  of  the  elasticity  of  the  air,  but  by 
his  distinction  of  the  elements  and  compounds  and  his 
definition  of  chemistry  as  the  science  of  the  composi- 
tion of  substances.  How  little  had  been  accomplished, 
however,  is  evident  from  the  fact  that  in  1750  the 
so-called  elements  —  earth,  air,  fire,  water  —  which 
Bacon  had  marked  for  examination  in  1620,  were 
still  unanalyzed,  and  that  no  advance  had  been  made 
beyond  his  conception  of  the  nature  of  heat,  the  ma- 
jority, indeed,  of  the  learned  world  holding  that  heat 
is  a  substance  (variously  identified  with  sulphur, 
carbon,  or  hydrogen)  rather  than  a  mode  of  motion. 

How  scientific  thought  succeeded  in  bringing  order 
out  of  confusion  and  chaos  in  the  subsequent  one 
hundred  years,  and  especially  at  the  beginning  of  the 
nineteenth  century,  can  well  be  illustrated  by  these 
very  matters,  the  study  of  combustion,  of  heat  as  a 
form  of  energy,  of  the  constituents  of  the  atmosphere, 
and  of  the  chemistry  of  water  and  of  the  earth. 

Reference  has  already  been  made  to  Black's  dis- 
covery of  carbonic  acid,  and  of  the  phenomena  which 


156         THE  HISTORY  OF  SCIENCE 

he  ascribed  to  latent  heat.  The  first  discovery  (1754) 
was  the  result  of  the  preparation  of  quicklime  in  the 
practice  of  medicine ;  the  second  (1761)  involving 
experiments  on  the  temperatures  of  melting  ice,  boil- 
ing water,  and  steam,  stimulated  Watt  in  his  improve- 
ment of  the  steam  engine.  In  1766  Joseph  Priestley 
began  his  study  of  airs,  or  gases.  In  the  following  year 
observation  of  work  in  a  brewery  roused  his  curiosity 
in  reference  to  carbonic  acid.  In  1772  he  experi- 
mented with  nitric  oxide.  In  the  previous  century 
Mayow  had  obtained  nitric  oxide  by  treating  iron 
with  nitric  acid.  He  had  then  introduced  this  gas 
into  ordinary  air  confined  over  water,  and  found  that 
the  mixture  suffered  a  reduction  of  volume.  Priestley 
applied  this  process  to  the  analysis  of  common  air, 
which  he  discovered  to  be  complex  and  not  simple. 
In  1774,  by  heating  red  oxide  of  mercury  by  means 
of  a  burning-glass,  he  obtained  a  gas  which  sup- 
ported combustion  better  than  common  air.  He  in- 
haled it,  and  experienced  a  sense  of  exhilaration. 
"  Who  can  tell,"  he  writes,  "  but  in  time  this  pure  air 
may  become  a  fashionable  article  in  luxury  ?  Hith- 
erto only  two  mice  and  myself  have  had  the  privilege 
of  breathing  it." 

The  Swedish  investigator  Scheele  had,  however, 
discovered  this  same  constituent  of  the  air  before 
1773.  He  thought  that  the  atmosphere  must  consist 
of  at  least  two  gases,  and  he  proved  that  carbonic 
acid  results  from  combustion  and  respiration.  In 
1772  the  great  French  scientist  Lavoisier  found  that 
sulphur,  when  burned,  gains  weight  instead  of  losing 
weight,  and  five  years  later  he  concluded  that  air 
consists  of -two  gases,  one  capable  of  absorption  by 


THE  REIGN  OF  LAW  157 

burning  bodies,  the  other  incapable  of  supporting 
combustion.  He  called  the  first  "oxygen."  In  his 
Elements  of  Chemistry  Lavoisier  gave  a  clear  ex- 
position of  his  system  of  chemistry  and  of  the 
discoveries  of  other  European  chemists.  After  his 
studies  the  atmosphere  was  no  longer  regarded  as 
mysterious  and  chaotic.  It  was  known  to  consist 
largely  of  oxygen  and  nitrogen,  and  to  contain  in 
addition  aqueous  vapor,  carbonic  acid,  and  ammonia 
which  might  be  brought  to  earth  by  rain. 

Cavendish  obtained  nitrogen  from  air  by  using 
nitric  oxide  to  remove  the  oxygen,  and  found  that 
air  consists  of  about  seventy-nine  per  cent  nitrogen 
and  about  twenty-one  per  cent  oxygen.  He  also  by 
use  of  the  electric  spark  caused  the  oxygen  and  ni- 
trogen of  the  air  to  unite  to  form  nitric  acid.  When 
the  nitrogen  was  exhausted  and  the  redundant  oxygen 
removed,  "  only  a  small  bubble  of  air  remained  un- 
absorbed."  Similarly  Cavendish  had  found  that  water 
results  from  the  combination  of  oxygen  and  hydrogen. 
Watt  had  likewise  held  that  water  is  not  an  element, 
but  a  compound  of  two  elementary  substances.  Thus 
the  great  masses,  —  earth,  air,  fire,  water,  —  assumed 
as  simple  by  many  philosophers  from  the  earliest 
times,  were  resolving  into  their  constituent  parts.  At 
the  same  time  other  problems  were  demanding  solu- 
tion. What  are  the  laws  of  chemical  combination? 
What  is  the  relation  of  heat  to  other  forms  of  energy? 
To  the  answering  of  these  questions  (as  of  those  from 
which  these  grew)  the  great  manufacturing  centers 
contributed,  and  no  city  more  potently  than  Man- 
chester through  Dalton  and  his  pupil  and  follower 
Joule. 


158         THE  HISTORY  OF  SCIENCE 

John  Dal  ton  (1766-1844)  was  born  in  Cumber- 
land, went  to  Kendal  to  teach  school  at  the  age  of 
fifteen,  and  remained  in  the  Lake  District  of  England 
till  1793.  In  this  region,  where  the  annual  rainfall 
exceeds  forty  inches,  and  in  some  localities  is  almost 
tropical,  the  young  student's  attention  was  early 
drawn  to  meteorology.  His  apparatus  consisted  of 
rude  home-made  rain-gauges,  thermometers,  and  ba- 
rometers. His  interest  in  the  heat,  moisture,  and 
constituents  of  the  atmosphere  continued  throughout 
life,  and  Dalton  made  in  all  some  200,000  meteoro- 
logical observations.  We  gain  a  clue  to  his  motive 
in  these  studies  from  a  letter  written  in  his  twenty- 
second  year,  in  which  he  speaks  of  the  advantages 
that  might  accrue  to  the  husbandman,  the  mariner, 
and  to  mankind  in  general  if  we  were  able  to  predict 
the  state  of  the  weather  with  tolerable  precision. 

In  1793  Dalton  took  up  his  permanent  residence 
in  Manchester,  and  in  that  year  appeared  his  first 
book,  Meteorological  Observations  and  Essays. 
Here  he  deals,  among  other  things,  with  rainfall,  the 
formation  of  clouds,  evaporation,  and  the  distribution 
and  character  of  atmospheric  moisture.  It  seemed 
to  him  that  aqueous  vapor  always  exists  as  a  distinct 
fluid  maintaining  its  identity  among  the  other  fluids 
of  the  atmosphere.  He  thought  of  atmospheric  mois- 
ture as  consisting  of  minute  drops  of  water,  or  glob- 
ules among  the  globules  of  oxygen  and  nitrogen.  He 
was  a  disciple  of  Newton's  (to  whom,  indeed,  Dalton 
had  some  personal  likeness),  who  looked  upon  matter 
as  consisting  of  "  solid,  massy,  hard,  impenetrable, 
movable  particles,  of  such  sizes  and  figures,  and  with 
such  other  properties,  and  in  such  proportion,  as 


THE  REIGN  OF  LAW  159 

most  conduced  to  the  end  for  which  God  formed 
them."  Dalton  was  so  much  under  the  influence  of 
the  idea  that  the  physical  universe  is  made  up  of 
these  indivisible  particles,  or  atoms,  that  his  biogra- 
pher describes  him  as  thinking  corpuscularly.  It  is 
probable  that  his  imagination  was  of  the  visualizing 
type  and  that  he  could  picture  to  himself  the  arrange- 
ment of  atoms  in  elementary  and  compound  substances. 

Now  Dalton's  master  had  taught  that  the  atoms  of 
matter  in  a  gas  (elastic  fluid)  repel  one  another  by 
a  force  increasing  in  proportion  as  their  distance 
diminishes.  How  did  this  teaching  apply  to  the  at- 
mosphere, which  Priestley  and  others  had  proved  to 
consist  of  three  or  more  gases?  Why  does  this  mix- 
ture appear  simple  and  homogeneous  ?  Why  does  not 
the  air  form  strata  with  the  oxygen  below  and  the 
nitrogen  above?  Cavendish  had  shown,  and  Dalton 
himself  later  proved,  that  common  air,  wherever  ex- 
amined, contains  oxygen  and  nitrogen  in  fairly  con- 
stant proportions. 

French  chemists  had  sought  to  apply  the  principle 
of  chemical  affinity  in -explaining  the  apparent  homo- 
geneity of  the  atmosphere.  They  supposed  that  oxygen 
and  nitrogen  entered  into  chemical  union,  the  one 
element  dissolving  the  other.  The  resultant  com- 
pound in  turn  dissolved  water ;  hence  the  phenomena 
of  evaporation.  Dalton  tried  in  vain  to  reconcile  this 
supposition  with  his  belief  in  the  atomic  nature  of 
matter.  He  drew  diagrams  combining  an  atom  of  oxy- 
gen with  an  atom  of  nitrogen  and  an  atom  of  aqueous 
vapor.  The  whole  atmosphere  could  not  consist  of 
such  groups  of  three  because  the  watery  particles 
were  but  a  small  portion  of  the  total  atmosphere. 


160         THE  HISTORY  OF  SCIENCE 

He  made  a  diagram  in  which  one  atom  of  oxygen  was 
combined  with  one  atom  of  nitrogen,  but  in  this  case 
the  oxygen  was  insufficient  to  satisfy  all  the  nitrogen 
of  the  atmosphere.  If  the  air  was  made  up  partly  of 
pure  nitrogen,  partly  of  a  compound  of  nitrogen  and 
oxygen,  and  partly  of  a  compound  of  nitrogen,  oxy- 
gen, and  aqueous  vapor,  then  the  triple  compound,  as 
heaviest,  would  collect  toward  the  surface  of  the  earth, 
and  the  double  compound  and  the  simple  substance 
would  form  two  strata  above.  If  to  the  compounds 
heat  were  added  in  the  hope  of  producing  an  un- 
stratified  mixture,  the  atmosphere  would  acquire  the 
specific  gravity  of  nitrogen  gas.  "In  short,"  says 
Dalton,  "  I  was  obliged  to  abandon  the  hypothesis 
of  the  chemical  constitution  of  the  atmosphere  alto- 
gether as  irreconcilable  to  the  phenomena." 

He  had  to  return  to  the  conception  of  the  indi- 
vidual particles  of  oxygen,  nitrogen,  and  water,  each 
a  center  of  repulsion.  Still  he  could  not  explain  why 
the  oxygen  did  not  gravitate  to  the  lowest  place,  the 
nitrogen  form  a  stratum  above,  and  the  aqueous  vapor 
swim  upon  the  top.  In  1801,  however,  Dalton  hit 
upon  the  idea  that  gases  act  as  vacua  for  one  another, 
that  it  is  only  like  particles  which  repel  each  other, 
atoms  of  oxygen  repelling  atoms  of  oxygen  and  atoms 
of  nitrogen  repelling  atoms  of  nitrogen  when  these 
gases  are  intermingled  in  the  atmosphere  just  as 
they  would  if  existing  in  an  unmixed  state.  "  Accord- 
ing to  this,  we  were  to  suppose  that  atoms  of  one  kind 
did  not  repel  the  atoms  of  another  kind,  but  only 
those  of  their  own  kind."  A  mixed  atmosphere  is  as 
free  from  stratifications,  as  though  it  were  really 
homogeneous. 


THE  REIGN  OF  LAW  161 

In  his  analyses  of  air  Dalton  made  use  of  the  old 
nitric  oxide  method.  In  1802  this  led  to  an  inter- 
esting discovery.  If  in  a  tube  .3  of  an  inch  wide  he 
mixed  100  parts  of  common  air  with  36  parts  of 
nitric  oxide,  the  oxygen  of  the  air  combined  with 
the  nitric  oxide,  and  a  residue  of  79  parts  of  atmos- 
pheric nitrogen  remained.  And  if  he  mixed  100 
parts  of  common  air  with  72  of  nitric  oxide,  but  in 
a  wide  vessel  over  water  (in  which  conditions  the 
combination  is  more  quickly  effected),  the  oxygen 
of  the  air  again  combined  with  the  nitric  oxide  and 
a  residue  of  79  parts  of  nitrogen  again  resulted.  But 
in  the  last  experiment,  if  less  than  72  parts  of  nitric 
oxide  be  employed,  there  will  be  a  residue  of  oxygen 
as  well  as  nitrogen ;  and  if  more  than  72,  there  will 
be  a  residue  of  nitric  oxide  in  addition  to  the  nitro- 
gen. In  the  words  of  Dalton,  "  oxygen  may  com- 
bine with  a  certain  portion  of  nitrous  gas  [as  he 
called  nitric  oxide],  or  with  twice  that  portion,  but 
with  no  intermediate  portion."" 

Naturally  these  experimental  facts  were  to  be  ex- 
plained in  terms  of  the  ultimate  particles  of  which 
the  various  gases  are  composed.  In  the  following 
year  Dalton  gave  graphic  representation  to  his  idea 
of  the  atomic  constitution  of  chemical  elements  and 
compounds. 

O  Hydrogen  CD  Nitrogen 

O  Oxygen  •  Carbon 

CD0  Nitric  oxide  ©•(•>  Carbonic  acid 
©0)0  Nitrous  oxide 

Much  against  Dalton's  will  his  method  of  indicating 
chemical  elements  and  their  combinations  had  to 


162         THE  HISTORY  OF  SCIENCE 

yield  to  a  method  introduced  by  the  great  Swedish 
chemist  Berzelius.  In  1837  Dalton  wrote :  "  Ber- 
zelius's  symbols  are  horrifying :  a  young  student  in 
chemistry  might  as  soon  learn  Hebrew  as  make  him- 
self acquainted  with  them.  They  appear  like  a  chaos 
of  atoms  .  .  .  and  to  equally  perplex  the  adepts  of 
science,  to  discourage  the  learner,  as  well  as  to  cloud 
the  beauty  and  simplicity  of  the  Atomic  Theory." 

Meantime  Dalton's  mind  had  been  turning  to  the 
consideration  of  the  relative  sizes  and  weights  of  the 
various  elements  entering  into  combination  with  one 
another.  He  argued  that  if  there  be  not  exactly  the 
same  number  of  atoms  of  oxygen  in  a  given  volume 
of  air  as  of  nitrogen  in  the  same  volume,  then  the 
sizes  of  the  particles  of  oxygen  must  be  different 
from  those  of  nitrogen.  His  interest  in  the  absorp- 
tion of  gases  by  water,  in  the  reciprocal  diffusion  of 
gases,  as  well  as  in  the  phenomena  of  chemical  com- 
bination, stimulated  Dalton  to  determine  the  relative 
size  and  weight  of  the  atoms  of  the  various  elements. 
Dalton  said  nothing  of  the  absolute  weight  of  the 
atom.  But  on  the  assumption  that  when  only  one 
compound  of  two  elements  is  known  to  exist,  the 
molecule  of  the  compound  consists  of  one  atom  of 
each  of  these  elements,  he  proceeded  to  investigate 
the  relative  weights  of  equal  numbers  of  the  two 
sorts  of  atoms.  In  1803  he  pursued  this  investiga- 
tion with  remarkable  success,  and  taking  hydrogen 
(the  lightest  gas  known  to  him)  as  unity,  he  arrived 
at  a  statement  of  the  relative  atomic  weights  of 
oxygen,  nitrogen,  carbon,  etc.  Dalton  thus  intro- 
duced into  the  study  of  chemical  combination  a  very 
definite  idea  of  quantitative  relationship.  By  hinj 


THE  REIGN  OF  LAW  163 

the  atomic  theory  of  the  constitution  of  matter  was 
made  definite  and  applicable  to  all  the  phenomena 
known  to  chemistry. 

During  the  following  months  he  returned  to  the 
study  of  those  cases  in  which  the  same  elements 
combine  to  form  more  than  one  compound.  We 
have  seen  that  oxygen  unites  with  nitric  oxide  to 
form  two  compounds,  and  that  into  the  one  com- 
pound twice  as  much  nitric  oxide  (by  weight)  enters 
as  into  the  other.  A  like  relation  was  found  in  the 
weight  of  oxygen  combining  with  carbon  in  the  two 
compounds  carbon  monoxide  and  carbonic  acid.  In 
the  summer  of  1804  he  investigated  the  composition 
of  two  compounds  of  hydrogen  and  carbon,  marsh 
gas  (methane)  and  olefiant  gas  (ethylene),  and 
found  that  the  first  contained  just  twice  as  much 
hydrogen  in  relation  to  the  carbon  as  the  second 
compound  contained.  In  a  series  of  compounds  of 
the  same  two  elements  one  atom  of  one  unites  with 
one,  two,  three,  or  more  atoms  of  the  other ;  that  is, 
a  simple  ratio  exists  between  the  weights  in  which 
the  second  element  enters  into  combination  with  the 
first.  This  law  of  multiple  proportions  afforded  con- 
firmation of  Dalton's  atomic  theory,  or  chemical 
theory  of  definite  proportions. 

"  Without  such  a  theory,"  says  Sir  Henry  Roscoe, 
"  modern  chemistry  would  be  a  chaos ;  with  it,  order 
reigns  supreme,  and  every  apparently  contradictory 
discovery  only  marks  out  more  distinctly  the  value 
and  importance  of  Dalton's  work."  In  1826  Sir 
Humphry  Davy  recognized  Dalton's  services  to  sci- 
ence in  the  following  terms :  "  Finding  that  in  cer- 
tain compounds  of  gaseous  bodies  the  same  elements 


164         THE  HISTORY  OF  SCIENCE 

always  combined  in  the  same  proportions,  and  that 
when  there  was  more  than  one  combination  the 
quantity  of  the  elements  always  had  a  constant  rela- 
tion,—  such  as  1  to  2,  or  1  to  3,  or  1  to  4,  —  he 
explained  this  fact  on  the  Newtonian  doctrine  of  in- 
divisible atoms;  and  contended  that,  the  relative 
weight  of  one  atom  to  that  of  any  other  atom  being 
known,  its  proportions  or  weight  in  all  its  combina- 
tions might  be  ascertained,  thus  making  the  statics 
of  chemistry  depend  upon  simple  questions  in  sub- 
traction or  multiplication  and  enabling  the  student 
to  deduce  an  immense  number  of  facts  from  a  few 
well-authenticated  experimental  results.  Mr.  Dai- 
ton's  permanent  reputation  will  rest  upon  his  having 
discovered  a  simple  principle  universally  applicable 
to  the  facts  of  chemistry,  in  fixing  the  propor- 
tions in  which  bodies  combine,  and  thus  laying  the 
foundation  for  future  labors  respecting  the  sublime 
and  transcendental  parts  of  the  science  of  corpuscu- 
lar motion.  His  merits  in  this  respect  resemble  those 
of  Kepler  in  astronomy." 

In  1808  Dalton's  atomic  theory  received  striking 
confirmation  through  the  investigations  of  the  French 
scientist  Gay-Lussac,  who  showed  that  gases,  under 
similar  circumstances  of  temperature  and  pressure, 
always  combine  in  simple  proportions  by  volume 
when  they  act  on  one  another,  and  that  when  the 
result  of  the  union  is  a  gas,  its  volume  also  is  in  a 
simple  ratio  to  the  volumes  of  its  components.  One 
of  Dalton's  friends  summed  up  the  result  of  Gray- 
Lussac's  research  in  this  simple  fashion  :  "  His  paper 
is  on  the  combination  of  gases.  He  finds  that  all  unite 
in  equal  bulks,  or  two  bulks  of  one  to  one  of  another, 


THE  REIGN  OF  LAW  165 

or  three  bulks  of  one  to  one  of  another."  When 
Dalton  had  investigated  the  relative  weights  with 
which  elements  combine,  he  had  found  no  simple 
arithmetical  relationship  between  atomic  weight  and 
atomic  weight.  When  two  or  more  compounds  of  the 
same  elements  are  formed,  Dalton  found,  however, 
as  we  have  seen,  that  the  proportion  of  the  element 
added  to  form  the  second  or  third  compound  is  a 
multiple  by  weight  of  the  first  quantity.  Gay-Lussac 
now  showed  that  gases,  uin  whatever  proportions 
they  may  combine,  always  give  rise  to  compounds 
whose  elements  by  volume  are  multiples  of  each 
other." 

In  1811  Avogadro,  in  an  essay  on  the  relative 
masses  of  atoms,  succeeded  in  further  confirming 
Dalton's  theory  and  in  explaining  the  atomic  basis  of 
Gay-Lussac's  discovery  of  simple  volume  relations  in 
the  formation  of  chemical  compounds.  According  to 
the  Italian  scientist  the  number  of  molecules  in  all 
gases  is  always  the  same  for  equal  volumes,  or  al- 
ways proportional  to  the  volumes,  it  being  taken  for 
granted  that  the  temperature  and  pressure  are  the 
same  for  each  gas.  Dalton  had  supposed  that  water 
is  formed  by  the  union  of  hydrogen  and  oxygen, 
atom  for  atom.  Gay-Lussac  found  that  two  volumes 
of  hydrogen  combined  with  one  volume  of  oxygen  to 
produce  two  volumes  of  water  vapor.  According  to 
Avogadro  the  water  vapor  contains  twice  as  many 
atoms  of  hydrogen  as  of  oxygen.  One  volume  of 
hydrogen  has  the  same  number  of  molecules  as  one 
volume  of  oxygen.  When  the  two  volumes  combine 
with  one,  the  combination  does  not  take  place,  as 
Dalton  had  supposed,  atom  for  atom,  but  each  half- 


166         THE  HISTORY  OF  SCIENCE 

molecule  of  oxygen  combines  with  one  molecule  of 
hydrogen.  The  symbol  for  water  is,  therefore,  not 
HO  but  H2O. 

Enough  has  been  said  to  establish  Dalton's  claim 
to  be  styled  a  great  lawgiver  of  chemical  science. 
His  influence  in  further  advancing  definitely  formu- 
lated knowledge  of  physical  phenomena  can  here  be 
indicated  only  in  part.  In  1800  he  wrote  a  paper 
On  the  Heat  and  Cold  produced  by  the  Mechanical 
Condensation  and  Rarefaction  of  Air.  This  con- 
tains, according  to  Dalton's  biographer,  the  first 
quantitative  statement  of  the  heat  evolved  by  com- 
pression and  the  heat  evolved  by  dilatation.  His  con- 
tribution to  the  theory  of  heat  has  been  stated  thus  : 
The  volume  of  a  gas  under  constant  pressure  ex- 
pands when  raised  to  the  boiling  temperature  by  the 
same  fraction  of  itself,  whatever  be  the  nature  of 
the  gas.  In  1798  Count  Rumford  had  reported  to 
the  Royal  Society  his  Enquiry  concerning  the  Source 
of  Heat  excited  by  Friction,  the  data  for  which  had 
been  gathered  at  Munich.  Interested  as  he  was  in 
the  practical  problem  of  providing  heat  for  the  homes 
of  the  city  poor,  Rumford  had  been  struck  by  the 
amount  of  heat  developed  in  the  boring-out  of  can- 
non at  the  arsenal.  He  concluded  that  anything 
which  could  be  created  indefinitely  by  a  process  of 
friction  could  not  be  a  substance,  such  as  sulphur  or 
hydrogen,  but  must  be  a  mode  of  motion.  In  the  same 
year  the  youthful  Davy  was  following  independently 
this  line  of  investigation  by  rubbing  two  pieces  of  ice 
together,  by  clock-work,  in  a  vacuum.  The  friction 
caused  the  ice  to  melt,  although  the  experiment  was 
undertaken  in  a  temperature  of  29°  Fahrenheit. 


THE  REIGN  OF  LAW  167 

For  James  Prescott  Joule  (1818-1889),  who  came 
of  a  family  of  brewers  and  was  early  engaged  him- 
self in  the  brewing  industry,  was  reserved,  however, 
the  distinction  of  discovering  the  exact  relation  be- 
tween heat  and  mechanical  energy.  After  having 
studied  chemistry  under  Dalton  at  Manchester,  he 
became  engrossed  in  physical  experimentation.  In 
1843  he  prepared  a  paper  On  the  Calorific  Effects 
of  Magneto-Electricity  and  on  the  Mechanical  Value 
of  Heat.  In  this  he  dealt  with  the  relations  between 
heat  and  the  ordinary  forms  of  mechanical  power, 
and  demonstrated  that  the  mechanical  energy  spent 
"  in  turning  a  magneto-electrical  machine  is  converted 
into  the  heat  evolved  by  the  passage  of  the  currents 
of  induction  through  its  coils  ;  and,  on  the  other  hand, 
that  the  motive  power  of  the  electro-magnetic  engine 
is  obtained  at  the  expense  of  the  heat  due  to  the 
chemical  reactions  of  the  battery  by  which  it  is 
worked."  In  1844  he  proceeded  to  apply  the  prin- 
ciples maintained  in  his  earlier  study  to  changes  of 
temperature  as  related  to  changes  in  the  density  of 
gases.  He  was  conscious  of  the  practical,  as  well  as 
the  theoretical,  import  of  his  investigation.  Indeed, 
it  was  through  the  determination  by  this  illustrious 
pupil  of  Dalton's  of  the  amount  of  heat  produced  by 
the  compression  of  gases  that  one  of  the  greatest  im- 
provements of  the  steam  engine  was  later  effected. 
Joule  felt  that  his  investigation  at  the  same  time  con- 
firmed the  dynamical  theory  of  heat  which  originated 
with  Bacon,  and  had  at  a  subsequent  period  been 
so  well  supported  by  the  experiments  of  Rumford, 
Davy,  and  others. 

Already,  in  this  paper  of  June,  1844,  Joule  had 


168         THE  HISTORY  OF  SCIENCE 

expressed  the  hope  of  ascertaining  the  mechanical 
equivalent  of  heat  with  the  accuracy  that  its  import- 
ance for  physical  science  demanded.  He  returned  to 
this  question  again  and  again.  According  to  his  final 
result  the  quantity  of  heat  required  to  raise  one  p'ound 
of  water  in  temperature  by  one  degree  Fahrenheit  is 
equivalent  to  the  mechanical  energy  required  to  raise 
772.55  pounds  through  a  distance  of  one  foot.  Heat 
was  thus  demonstrated  to  be  a  form  of  energy,  the 
relation  being  constant  between  it  and  mechanical 
energy.  Mechanical  energy  may  be  converted  into 
heat ;  if  heat  disappears,  some  other  form  of  energy, 
equivalent  in  amount  to  the  heat  lost,  must  replace  it. 
The  doctrine  that  a  certain  quantity  of  heat  is  always 
equivalent  to  a  certain  amount  of  mechanical  energy 
is  only  a  special  case  of  the  Law  of  the  Conserva- 
tion of  Energy,  first  clearly  enunciated  by  Joule  and 
Helmholtz  in  1847,  and  generally  regarded  as  the 
most  important  scientific  discovery  of  the  nineteenth 
century. 

Roscoe,  referring  to  the  two  life-sized  marble  stat- 
ues which  face  each  other  in  the  Manchester  Town 
Hall,  says  with  pardonable  pride :  "  Thus  honor  is 
done  to  Manchester's  two  greatest  sons  —  to  Dai- 
ton,  the  founder  of  modern  Chemistry  and  of  the 
Atomic  Theory,  and  the  discoverer  of  the  laws  of 
chemical  combining  proportions ;  to  Joule,  the  founder 
of  modern  Physics  and  the  discoverer  of  the  Law  of 
the  Conservation  of  Energy." 


THE   REIGN   OF   LAW  169 


REFERENCES 

Alembic  Club  Reprints,  Foundations  of  the  Atomic  Theory. 
Joseph  Priestley,  Experiments  and  Observations  on  Different 

Kinds  of  Air. 
Sir  William  Ramsay,  The  Gases  of  the  Atmosphere  and  the  History 

of  their  Discovery. 

Sir  Henry  E.  Roscoe,  John  Dalton. 
Sir  E.  Thorpe,  Essays  in  Historical  Chemistry. 


CHAPTER  XIII 

THE   SCIENTIST SIB   HUMPHRY   DAVY 

HUMPHRY  DAVY  (1778-1829)  was  born  in  Corn- 
wall, a  part  of  England  known  for  its  very  mild  cli- 
mate and  the  combined  beauty  and  majesty  of  its 
scenery.  On  either  side  of  the  peninsula  the  Atlantic 
in  varying  mood  lies  extended  in  summer  sunshine, 
or  from  its  shroud  of  mist  thunders  on  the  black 
cliffs  and  their  time-sculptured  sandstones.  From  the 
coast  inland,  stretch,  between  flowered  lanes  and 
hedges,  rolling  pasture-lands  of  rich  green  made  all 
the  more  vivid  by  the  deep  reddish  tint  of  the 
ploughed  fields.  In  Penzance,  then  a  town  of  about 
three  thousand  inhabitants,  and  in  its  picturesque 
vicinity,  the  early  years  of  Davy's  life  were  passed. 
Across  the  bay  rose  the  great  vision  of  the  guarded 
mount  (St.  Michael's)  of  which  Milton's  verse 
speaks.  Farther  to  the  east  lay  Lizard  Head,  the 
southernmost  promontory  of  England,  and  a  few 
miles  to  the  north  St.  Ives  with  its  sweep  of  sandy 
beach ;  while  not  far  to  the  west  of  Penzance  Land's 
End  stood  sentry  "  'Twixt  two  unbounded  seas." 
The  youthful  Davy  was  keenly  alive  to  the  charms 
of  his  early  environment,  and  his  genius  was  sus- 
ceptible to  the  belief  in  supernatural  agencies  native 
to  the  imaginative  Celtic  people  among  whom  he 
was  reared.  As  a  precocious  child  of  five  he  impro- 
vised rhymes,  and  as  a  youth  set  forth  in  excellent 
verse  the  glories  of  Mount's  Bay :  — 


THE  SCIENTIST  171 

"  There  did  I  first  rejoice  that  I  wag  born 
Amidst  the  majesty  of  azure  seas." 

Davy  received  what  is  usually  called  a  liberal  edu- 
cation, putting  in  nine  years  in  the  Penzance  and 
one  year  in  the  Truro  Grammar  School.  His  best 
exercises  were  translations  from  the  classics  into 
English  verse.  He  was  rather  idle,  fond  of  fishing 
(an  enthusiasm  he  retained  throughout  life)  and 
shooting,  and  less  appreciated  and  beloved  by  his 
masters  than  by  his  school-fellows,  who  recognized 
his  wonderful  abilities,  sought  his  aid  in  their  Latin 
compositions  (as  well  as  in  the  writing  of  letters  and 
valentines),  and  listened  eagerly  to  his  imaginative 
tales  of  wonder  and  horror.  Years  later  he  wrote  to 
his  mother :  "  After  all,  the  way  in  which  we  are 
taught  Latin  and  Greek  does  not  much  influence 
the  important  structure  of  our  minds.  I  consider  it 
fortunate  that  I  was  left  much  to  myself  when  a 
child,  and  put  upon  no  particular  plan  of  study,  and 
that  I  enjoyed  much  idleness  at  Mr.  Coryton's  school. 
I  perhaps  owe  to  these  circumstances  the  little  talents 
that  I  have  and  their  peculiar  application." 

When  Davy  was  about  sixteen  years  old,  his  fa- 
ther died,  leaving  the  widow  and  her  five  children, 
of  whom  Humphry  was  the  eldest,  with  very  scanty 
provision.  The  mind  of  the  youth  seemed  to  under- 
go an  immediate  change.  He  expressed  his  resolu- 
tion (which  he  nobly  carried  out)  to  play  his  part 
as  son  and  brother.  Within  a  few  weeks  he  became 
apprenticed  to  an  apothecary  and  surgeon,  and,  hav- 
ing thus  found  his  vocation,  drew  up  his  own  par- 
ticular plan  of  self-education,  to  which  he  rigidly 
adhered.  His  brother,  Dr.  John  Davy,  bears  witness 


172         THE  HISTORY  OF  SCIENCE 

that  the  following  is  transcribed  from  a  notebook 
of  Humphry's,  bearing  the  date  of  the  same  year  as 
his  apprenticeship  (1795)  :  — 

1.  Theology  or  Religion       )        Taught  by  Nature. 
Ethics  or  Moral  Virtues  )  by  Revelation. 

2.  Geography. 

3.  My  Profession  — 

1.  Botany.  2.  Pharmacy.  3.  Nosology.  4.  Anatomy. 
5.  Surgery.  6.  Chemistry. 

4.  Logic. 

5.  Language,  etc. 

A  series  of  essays  which  Davy  wrote  in  pursuing 
his  scheme  of  self -culture  proves  how  rapidly  his  mind 
drew  away  from  the  superstitions  which  character- 
ized the  masses  of  the  people  among  whom  he  lived. 
He  had  as  a  boy  been  haunted  by  the  fear  of  mon- 
sters and  witches  in  which  the  credulous  of  all  classes 
then  believed.  His  notebook  shows  that  he  was  now 
subjecting  to  examination  the  religious  and  political 
opinions  of  his  time.  He  composed  essays  on  the 
immortality  and  immateriality  of  the  soul,  on  gov- 
ernments, on  the  credulity  of  mortals,  on  the  de- 
pendence of  the  thinking  powers  on  the  organiza- 
tion of  the  body,  on  the  ultimate  end  of  being,  on 
happiness,  and  on  moral  obligation.  He  studied  the 
writings  of  Locke,  Hartley,  Berkeley,  Hume,  Hel- 
vetius,  Condorcet,  and  Reid,  and  knew  something  of 
German  philosophy.  It  was  not  till  he  was  nineteen 
that  Davy  entered  on  the  experimental  study  of 
chemistry. 

Guided  by  the  Elements  of  Lavoisier,  encouraged 
by  the  friendship  of  Gregory  Watt  (a  son  of  James 
Watt)  and  by  another  gentleman  of  university  edu- 


THE  SCIENTIST  173 

cation,  stimulated  by  contact  with  the  Cornish  min- 
ing industry,  Davy  pursued  this  new  study  with  zeal, 
and  within  a  few  months  had  written  two  essays  full 
of  daring  generalizations  on  the  physical  sciences. 
These  were  published  early  in  1790.  Partly  on  the 
basis  of  the  ingenious  experiment  mentioned  in  the 
preceding  chapter,  he  came  to  the  conclusion  that 
"  Heat,  or  that  power  which  prevents  the  actual 
contact  of  the  corpuscles  of  bodies,  and  which  is  the 
cause  of  our  peculiar  sensations  of  heat  and  cold, 
may  be  defined  as  a  peculiar  motion,  probably  a  vi- 
bration, of  the  corpuscles  of  bodies,  tending  to  sepa- 
rate them."  Other  passages  might  be  quoted  from 
these  essays  to  show  how  the  gifted  youth  of  nineteen 
anticipated  the  science  of  subsequent  decades,  but  in 
the  main  these  early  efforts  were  characterized  by 
the  faults  of  overwrought  speculation  and  incomplete 
verification.  He  soon  regretted  the  premature  pub- 
lication of  his  studies.  "  When  I  consider,"  he  wrote, 
"  the  variety  of  theories  that  may  be  formed  on  the 
slender  foundation  of  one  or  two  facts,  I  am  con- 
vinced that  it  is  the  business  of  the  true  philosopher 
to  avoid  them  altogether.  It  is  more  laborious  to 
accumulate  facts  than  to  reason  concerning  them ; 
but  one  good  experiment  is  of  more  value  than  the 
ingenuity  of  a  brain  like  Newton's." 

In  the  mean  time  Davy  had  been  chosen  superin- 
tendent of  the  Pneumatic  Institution  at  Bristol  by 
Dr.  Beddoes,  its  founder.  It  was  supported  by  the 
contributions  of  Thomas  Wedgwood  and  other  dis- 
tinguished persons,  and  aimed  at  discovering  by 
means  of  experiment  the  physiological  effect  of  in- 
haling different  gases,  or  "  factitious  airs,"  as  they 


174         THE  HISTORY  OF  SCIENCE 

were  called.  The  founding  of  such  an  establishment 
has  been  termed  a  scientific  aberration,  but  the  use 
now  made  in  medical  practice  of  oxygen,  nitrous 
oxide,  chloroform,  and  other  inhalations  bears  wit- 
ness to  the  sanity  of  the  sort  of  research  there  set 
on  foot.  Even  before  going  to  Bristol,  Davy  had  in- 
haled small  quantities  of  nitrous  oxide  mixed  with 
air,  in  spite  of  the  fact  that  this  gas  had  been  held 
by  a  medical  man  to  be  the  "  principle  of  contagion." 
He  now  carried  on  a  series  of  tests,  and  finally  un- 
dertook an  extended  experiment  with  the  assistance 
of  a  doctor.  In  an  air-tight  or  box-chamber  he  in- 
haled great  quantities  of  the  supposedly  dangerous 
gas.  After  he  had  been  in  the  box  an  hour  and  a 
quarter,  he  respired  twenty  quarts  of  pure  nitrous 
oxide.  He  described  the  experience  in  the  following 
words :  — 

"  A  thrilling,  extending  from  the  chest  to  the  ex- 
tremities, was  almost  immediately  produced.  I  felt 
a  sense  of  tangible  extension  highly  pleasurable  in 
every  limb;  my  visible  impressions  were  dazzling, 
and  apparently  magnified ;  I  heard  every  sound  in 
the  room,  and  was  perfectly  aware  of  my  situation. 
By  degrees,  as  the  pleasurable  sensations  increased, 
I  lost  all  connection  with  external  things ;  trains  of 
vivid  visible  images  rapidly  passed  through  my  mind, 
and  were  connected  with  words  in  such  a  manner,  as 
to  produce  perceptions  perfectly  novel.  I  existed  in 
a  world  of  newly  connected  and  newly  modified  ideas : 
I  theorized,  I  imagined  that  I  made  discoveries. 
"When  I  was  awakened  from  this  semi-delirious 
trance  by  Dr.  Kinglake,  who  took  the  bag  from  my 
mouth,  indignation  and  pride  were  the  first  feelings 


THE  SCIENTIST  175 

produced  by  the  sight  of  the  persons  about  me.  My 
emotions  were  enthusiastic  and  sublime,  and  for  a 
minute  I  walked  round  the  room  perfectly  regard- 
less of  what  was  said  to  me.  As  I  recovered  my 
former  state  of  mind,  I  felt  an  inclination  to  com- 
municate the  discoveries  I  had  made  during  the  ex- 
periment. I  endeavored  to  recall  the  ideas :  they 
were  feeble  and  indistinct ;  one  collection  of  terms, 
however,  presented  itself ;  and  with  the  most  intense 
belief  and  prophetic  manner,  I  exclaimed  to  Dr. 
Kinglake,  'Nothing  exists  but  thoughts  !  The  uni- 
verse is  composed  of  impressions,  ideas,  pleasures 
and  pains  ! ' 

Davy  aroused  the  admiration  and  interest  of  every 
one  who  met  him.  A  literary  man  to  whom  he  was 
introduced  shortly  after  his  arrival  in  Bristol  spoke 
of  the  intellectual  character  of  the  young  man's  face. 
His  eye  was  piercing,  and  when  he  was  not  engaged 
in  conversation,  its  expression  indicated  abstraction, 
as  though  his  mind  were  pursuing  some  severe  train 
of  thought  scarcely  to  be  interrupted  by  external  ob- 
jects ;  "  and,"  this  writer  adds,  "  his  ingenuousness 
impressed  me  as  much  as  his  mental  superiority." 
Mrs.  Beddoes,  a  gay,  witty,  and  elegant  lady,  and 
an  ardent  admirer  of  the  youthful  scientist,  was  a 
sister  of  Maria  Edgeworth.  The  novelist's  tolerance 
of  Davy's  enthusiasm  soon  passed  into  a  clear  recog- 
nition of  his  commanding  genius.  Coleridge,  Southey, 
and  other  congenial  friends,  whom  the  chemist  met 
under  Dr.  Beddoes'  roof,  shared  in  the  general  ad- 
miration of  his  mental  and  social  qualities.  Southey 
spoke  of  him  as  a  miraculous  young  man,  at  whose 
talents  he  could  only  wonder.  Coleridge,  when  asked 


176         THE  HISTORY  OF  SCIENCE 

how  Davy  compared  with  the  cleverest  men  he  had 
met  on  a  visit  to  London,  replied  expressively : 
"  Why,  Davy  can  eat  them  all !  There  is  an  energy, 
an  elasticity  in  his  mind,  which  enables  him  to  seize 
on  and  analyze  all  questions,  pushing  them  to  their 
legitimate  consequences.  Every  subject  in  Davy's 
mind  has  the  principle  of  vitality.  Living  thoughts 
spring  up  like  turf  under  his  feet."  He  thought  that 
if  Davy  had  not  been  the  first  chemist  he  would 
have  been  the  first  poet  of  the  age.  Their  corre- 
spondence attests  the  intimate  interchange  of  ideas 
and  sentiments  between  these  two  men  of  genius,  so 
different,  yet  with  so  much  in  common. 

In  1801  Davy  was  appointed  assistant  lecturer 
in  chemistry  at  the  Royal  Institution  (Albemarle 
Street,  London),  which  had  been  founded  from  phil- 
anthropic motives  by  Count  Rumford  in  1799.  Its 
aim  was  to  promote  the  application  of  science  to  the 
common  purposes  of  life.  Its  founder  desired  while 
benefiting  the  poor  to  enlist  the  sympathies  of  the 
fashionable  world.  Davy,  with  a  zeal  for  the  cause 
of  humanity  and  a  clear  recognition  of  the  value  of 
a  knowledge  of  chemistry  in  technical  industries  and 
other  daily  occupations,  lent  himself  readily  to  the 
founder's  plans.  His  success  as  a  public  expositor 
of  science  soon  won  him  promotion  to  the  professor- 
ship of  chemistry  in  the  new  institution,  and  through 
his  influence  an  interest  in  scientific  investigation 
became  the  vogue  of  London  society.  His  popularity 
as  a  lecturer  was  so  great  that  his  best  friends  feared 
that  the  head  of  the  brilliant  provincial  youth  of 
twenty-two  might  be  turned  by  the  adulation  of 
which  he  soon  became  the  object.  "  I  have  read," 


THE  SCIENTIST  177 

writes  his  brother,  "copies  of  verses  addressed  to 
him  then,  .  .  .  anonymous  effusions,  some  of  them 
displaying  much  poetical  taste  as  well  as  fervor  of 
writing,  and  all  showing  the  influence  which  his  ap- 
pearance and  manner  had  on  the  more  susceptible 
of  his  audience." 

His  study  of  the  tanning  industry  (1801-1802) 
and  his  lectures  on  agricultural  chemistry  (1803— 
1813)  are  indicative  of  the  early  purpose  of  the 
Royal  Institution  and  of  Davy's  lifelong  inclination. 
The  focus  of  his  scientific  interest,  however,  rested 
on  the  furtherance  of  the  application  of  the  electrical 
studies  of  Galvani  and  Volta  in  chemical  analysis. 
In  a  letter  to  the  chairman  of  managers  of  the  Royal 
Institution  Volta  had  in  1800  described  his  voltaic 
pile  made  up  of  a  succession  of  zinc  and  copper  plates 
in  pairs  separated  by  a  moist  conductor,  and  before 
the  end  of  the  same  year  Nicholson  and  Carlisle  had 
employed  an  electric  current,  produced  by  this  newly 
devised  apparatus,  in  the  decomposition  of  water  into 
its  elements. 

In  the  spring  of  the  following  year  the  Philosophi- 
cal Magazine  states :  "  We  have  also  to  notice  a 
course  of  lectures,  just  commenced  at  the  institution, 
on  a  new  branch  of  philosophy  —  we  mean  Galvanic 
Phenomena.  On  this  interesting  branch  Mr.  Davy 
(late  of  Bristol)  gave  the  first  lecture  on  the  25th  of 
April.  He  began  with  the  history  of  Galvanism,  de- 
tailed the  successive  discoveries,  and  described  the  dif- 
ferent methods  of  accumulating  influence.  .  .  .  He 
showed  the  effects  of  galvanism  on  the  legs  of  frogs, 
and  exhibited  some  interesting  experiments  on  the 
galvanic  effects  on  the  solutions  of  metals  in  acids." 


178         THE  HISTORY  OF  SCIENCE 

In  a  paper  communicated  to  the  Royal  Society  in 
1806,  On  Some  Chemical  Agencies  of  Electricity ', 
Davy  put  on  record  the  result  of  years  of  experiment. 
For  example,  as  stated  by  his  biographer,  he  had  con- 
nected a  cup  of  gypsum  with  one  of  agate  by  means 
of  asbestos,  and  filling  each  with  purified  water,  had 
inserted  the  negative  wire  of  the  battery  in  the 
agate  cup,  and  the  positive  wire  in  that  of  the  sul- 
phate of  lime.  In  about  four  hours  he  had  found  a 
strong  solution  of  lime  in  the  agate  cup,  and  sul- 
phuric acid  in  the  cup  of  gypsum.  On  his  reversing 
the  arrangement,  and  carrying  on  the  process  for  a 
similar  length  of  time,  the  sulphuric  acid  appeared  in 
the  agate  cup,  and  the  solution  of  lime  on  the  opposite 
side.  It  was  thus  that  he  studied  the  transfer  of  cer- 
tain of  the  constituent  parts  of  bodies  by  the  action 
of  electricity.  "It  is  very  natural  to  suppose,"  says 
Davy,  "  that  the  repellent  and  attractive  energies  are 
communicated  from  one  particle  to  another  particle 
of  the  same  kind,  so  as  to  establish  a  conducting 
chain  in  the  fluid.  There  may  be  a  succession  of 
decompositions  and  recompositions  before  the  elec- 
trolysis is  complete." 

The  publication  of  this  paper  in  1806  attracted 
much  attention  abroad,  and  gained  for  him  —  in  spite 
of  the  fact  that  England  and  France  were  then  at 
war  —  a  medal  awarded,  under  an  arrangement  insti- 
tuted by  Napoleon  a  few  years  previously,  for  the  best 
experimental  work  on  the  subject  of  electricity. 
"  Some  people,"  said  Davy,  "  say  I  ought  not  to  ac- 
cept this  prize;  and  there  have  been  foolish  para- 
graphs in  the  papers  to  that  effect ;  but  if  the  two 
countries  or  governments  are  at  war,  the  men  of 


THE  SCIENTIST  179 

science  are  not.  That  would,  indeed,  be  a  civil  war 
of  the  worst  description:  we  should  rather,  through 
the  instrumentality  of  men  of  science,  soften  the  as- 
perities of  national  hostility." 

In  the  following  year  Davy  reported  other  chemi- 
cal changes  produced  by  electricity;  he  had  suc- 
ceeded in  decomposing  the  fixed  alkalis  and  discover- 
ing the  elements  potassium  and  sodium.  To  analyze 
a  small  piece  of  pure  potash  slightly  moist  from  the 
atmosphere,  he  had  placed  it  on  an  insulated  platinum 
disk  connected  with  the  negative  side  of  a  voltaic 
battery.  A  platinum  wire  connected  with  the  positive 
side  was  brought  in  contact  with  the  upper  surface 
of  the  alkali.  "  The  potash  began  to  fuse  at  both  its 
points  of  electrization."  At  the  lower  (negative)  sur- 
face small  globules  having  a  high  metallic  luster  like 
quicksilver  appeared,  some  of  which  burned  with  ex- 
plosion and  flame  while  others  remained  and  became 
tarnished.  When  Davy  saw  these  globules  of  a  hith- 
erto unknown  metal,  he  danced  about  the  laboratory 
in  ecstasy  and  for  some  time  was  too  much  excited 
to  continue  his  experiments. 

After  recovering  from  a  very  severe  illness,  owing 
in  the  judgment  of  some  to  overapplication  to  experi- 
mental science,  and  in  his  own  judgment  to  a  visit 
to  Newgate  Prison  with  the  purpose  of  improving  its 
sanitary  condition,  Davy  made  an  investigation  of  the 
alkaline  earths.  He  failed  in  his  endeavor  to  obtain 
from  these  sources  pure  metals,  but  he  gave  names 
to  barium,  strontium,  calcium,  and  magnesium,  con- 
jecturing that  the  alkaline  earths  were,  like  potash 
and  soda,  metallic  oxides.  In  addition  Davy  antici- 
pated the  isolation  of  silicon,  aluminium,  and  zirco- 


180         THE  HISTORY  OF  SCIENCE 

nium.  No  doubt  what  gave  special  zest  to  his  study 
of  the  alkalis  was  the  hope  of  overthrowing  the  doc- 
trine of  French  chemists  that  oxygen  was  the  essen- 
tial element  of  every  acid.  Lavoisier  had  given  it, 
indeed,  the  name  oxygen  (acid-producer)  on  that  sup- 
position. Davy  showed,  however,  that  this  element  is 
a  constituent  of  many  alkalis. 

In  1810  he  advanced  his  controversy  by  explaining 
the  nature  of  chlorine.  Discovered  long  before  by 
the  indefatigable  Scheele,  it  bore  at  the  beginning  of 
the  nineteenth  century  the  name  oxymuriatic  acid. 
Davy  proved  that  it  contained  neither  oxygen  nor 
muriatic  (hydrochloric)  acid  (though,  as  we  know, 
it  forms,  with  hydrogen,  muriatic  acid).  He  gave 
the  name  chlorine  because  of  the  color  of  the  gas 
(^Xcopcfc,  pale  green).  Davy  studied  later  the  com- 
pounds of  fluorine,  and  though  unable  to  isolate  the 
element,  conjectured  its  likeness  to  chlorine. 

He  lectured  before  the  Dublin  Society  in  1810, 
and  again  in  the  following  year ;  on  the  occasion  of 
his  second  visit  receiving  the  degree  of  LL.D.  from 
Trinity  College.  He  was  knighted  in  the  spring  of 
1812,  and  was  married  to  a  handsome,  intellectual, 
and  wealthy  lady.  He  was  appointed  Honorary  Pro- 
fessor of  Chemistry  at  the  Royal  Institution.  His  new 
independence  gave  him  full  liberty  to  pursue  his 
scientific  interests.  Toward  the  close  of  1812  he 
writes  to  Lady  Davy :  — 

"Yesterday  I  began  some  new  experiments  to 
which  a-  very  interesting  discovery  and  a  slight  acci- 
dent put  an  end.  I  made  use  of  a  compound  more 
powerful  than  gunpowder  destined  perhaps  at  some 
time  to  change  the  nature  of  war  and  influence  the 


THE  SCIENTIST  181 

state  of  society.  An  explosion  took  place  which  has 
done  me  no  other  harm  than  that  of  preventing  me 
from  working  this  day  and  the  effects  of  which  will 
be  gone  to-morrow  and  which  I  should  not  mention 
at  all,  except  that  you  may  hear  some  foolish  exag- 
gerated account  of  it,  for  it  really  is  not  worth  men- 
tioning. .  .  ."  The  compound  on  the  investigation 
of  which  he  was  then  engaged  is  now  known  as  the 
trichloride  of  nitrogen. 

In  the  autumn  of  1813  Sir  Humphry  and  Lady 
Davy,  accompanied  by  Michael  Faraday,  who  on 
Davy's  recommendation  had  in  the  spring  of  the 
same  year  received  a  post  at  the  Royal  Institution, 
set  out,  in  spite  of  the  continuance  of  the  war,  on  a 
Continental  tour.  At  Paris  Sir  Humphry  was  wel- 
comed by  the  French  scientists  with  every  mark  of 
distinction.  A  substance  which  had  been  found  in 
the  ashes  of  seaweed  two  years  previously,  by  a  soap- 
boiler and  manufacturer  of  saltpeter,  was  submitted 
to  Davy  for  chemical  examination.  Until  Davy's 
arrival  in  Paris  little  had  been  done  to  determine 
its  real  character.  On  December  6  Gay-Lussac  pre- 
sented a  brief  report  on  the  new  substance,  which 
he  named  iode  and  considered  analogous  to  chlorine. 
Davy,  working  with  almost  incredible  rapidity  in 
the  presence  of  his  rivals,  was  able  a  week  later  to 
sketch  the  chief  characters  of  this  new  element,  now 
known  by  the  name  he  chose  for  it  —  iodine. 

We  have  passed  over  his  investigation  of  boracie 
acid,  ammonium  nitrate,  and  other  compounds;  we 
can  merely  mention  in  passing  his  later  studies  of 
the  diamond  and  other  forms  of  carbon,  of  the 
chemical  constituents  of  the  pigments  used  by  the 


182         THE  HISTORY  OF  SCIENCE 

ancients,  his  investigation  of  the  torpedo  fish,  and  his 
anticipation  of  the  arc  light. 

It  seems  fitting  that  Sir  Humphry  Davy  should 
be  popularly  remembered  for  his  invention  of  the 
miner's  safety-lamp.  At  the  beginning  of  the  nine- 
teenth century  the  development  of  the  iron  industry, 
the  increasing  use  of  the  steam  engine  and  of  ma- 
chinery in  general  led  to  great  activity  and  enter- 
prise in  the  working  of  the  coal  mines.  Colliery  ex- 
plosions of  fire-damp  (marsh  gas)  became  alarmingly 
frequent,  especially  in  the  north  of  England.  The 
mine-owners  in  some  cases  sought  to  suppress  the 
news  of  fatalities.  A  society,  however,  was  formed 
to  protect  the  miners  from  injury  through  gas  explo- 
sions, and  Davy  was  asked  for  advice.  On  his  return 
from  the  Continent  in  1815  he  applied  himself  en- 
ergetically to  the  matter.  He  visited  the  mines  and 
analyzed  the  gas.  He  found  that  fire-damp  explodes 
only  at  high  temperature,  and  that  the  flame  of  this 
explosive  mixture  will  not  pass  through  small  aper- 
tures. A  miner's  lamp  was  therefore  constructed 
with  wire  gauze  about  the  flame  to  admit  air  for 
combustion.  The  fire-damp  entering  the  gauze 
burned  quietly  inside,  but  could  not  carry  a  high 
enough  temperature  through  the  gauze  to  explode 
the  large  quantity  outside.  To  one  of  the  members 
of  the  philanthropic  society  which  had  appealed  to 
him  Davy  wrote :  "  I  have  never  received  so  much 
pleasure  from  the  result  of  any  of  my  chemical  la- 
bours ;  for  I  trust  the  cause  of  humanity  will  gain 
something  by  it." 

Davy  was  elected  President  of  the  Royal  Society 
in  1820,  and  retained  that  dignity  till  he  felt  com- 


THE  SCIENTIST  183 

pelled  by  ill  health  to  relinquish  it  in  1827.  "  It  was 
his  wish,"  says  his  brother,  "  to  have  seen  the  Royal 
Society  an  efficient  establishment  for  all  the  great 
practical  purposes  of  science,  similar  to  the  college 
contemplated  by  Lord  Bacon,  and  sketched  in  his 
New  Atlantis  ;  having  subordinate  to  it  the  Royal 
Observatory  at  Greenwich  for  astronomy ;  the  Brit- 
ish Museum,  for  natural  history,  in  its  most  exten- 
sive acceptation." 

Sir  Humphry  Davy,  after  a  life  crowded  with 
splendid  achievements,  died  at  Geneva  in  1829  with 
many  of  his  noblest  dreams  unfulfilled.  Fortunately 
in  Michael  Faraday,  who  is  sometimes  referred  to 
as  the  greatest  of  his  discoveries,  he  had  a  successor 
who  was  fully  adequate  to  the  task  of  furthering  the 
various  investigations  that  his  genius  had  set  on 
foot,  and  who,  to  the  majority  of  men  of  mature 
mind,  is  no  less  personally  interesting  than  the  Cor- 
nish scientist,  poet,  and  philosopher. 

REFERENCES 

John  Davy,  Works  of  Sir  Humphry  Davy. 

John  Davy,  Fragmentary  Remains,  literary  and  scientific,  of  Sir 

Humphry  Davy,  Bart. 
Bence  Jones,  Life  and  Letters  of  Faraday. 
John  Tyndall,  Faraday  as  a  Discoverer. 
E.  v.  Meyer,  History  of  Chemistry. 
S.  P.  Thompson,  Michael  Faraday  ;  his  Life  and  Work. 
Sir  Edward  Thorpe,  Humphry  Davy,  Poet  and  Philosopher. 


CHAPTER  XIV 

SCIENTIFIC    PREDICTION THE   DISCOVERY    OF 

NEPTUNE 

UNDER  this  heading  we  have  to  consider  a  single 
illustration  —  the  prediction,  and  the  discovery,  in 
1846,  of  the  planet  Neptune.  This  event  roused 
great  enthusiasm  among  scientists  as  well  as  in  the 
popular  mind,  afforded  proof  of  the  reliability  of  the 
Newtonian  hypothesis,  and  demonstrated  the  preci- 
sion to  which  the  calculation  of  celestial  motions  had 
attained.  Scientific  law  appeared  not  merely  as  a 
formulation  and  explanation  of  observed  phenom- 
ena but  as  a  means  for  the  discovery  of  new  truths. 
"Would  it  not  be  admirable,"  wrote  Valz  to  Arago 
in  1835,  "to  arrive  thus  at  a  knowledge  of  the  ex- 
istence of  a  body  which  cannot  be  perceived  ?  " 

The  prediction  and  discovery  of  Neptune,  to  which 
many  minds  contributed,  and  which  has  been  de- 
scribed with  a  show  of  justice  as  a  movement  of  the 
times,  arose  from  the  previous  discovery  of  the  planet 
Uranus  by  Sir  William  Herschel  in  1781.  After 
that  event  Bode  suggested  that  it  was  possible  other 
astronomers  had  observed  Uranus  before,  without 
recognizing  it  as  a  planet.  By  a  study  of  the  star 
catalogues  this  conjecture  was  soon  verified.  It  was 
found  that  Flamsteed  had  made,  in  1690,  the  first 
observation  of  the  heavenly  body  now  called  Uranus. 
Ultimately  it  was  shown  that  there  were  at  least 
seventeen  similar  observations  prior  to  1781. 


SCIENTIFIC  PREDICTION  185 

It  might  naturally  be  supposed  that  these  so- 
called  ancient  observations  would  lead  to  a  ready 
determination  of  the  planet's  orbit,  mass,  mean  dis- 
tance, longitude  with  reference  to  the  sun,  etc.  The 
contrary,  however,  seemed  to  be  the  case.  When 
Alexis  Bouvard,  the  associate  of  Laplace,  prepared 
in  1821  tables  of  Uranus,  Jupiter,  and  Saturn  on 
the  principles  of  the  Mecanique  Celeste,  he  was  un- 
able to  fix  an  orbit  for  Uranus  which  would  harmo- 
nize with  the  data  of  ancient  and  modern  observa- 
tions, that  is,  those  antecedent  and  subsequent  to 
Herschel's  discovery  in  1781.  If  he  computed  an 
orbit  from  the  two  sets  of  data  combined,  the  re- 
quirements of  the  earlier  observations  were  fairly  well 
met,  but  the  later  observations  were  not  represented 
with  sufficient  precision.  If  on  the  other  hand  only 
the  modern  data  were  taken  into  account,  tables 
could  be  constructed  meeting  all  the  observations 
subsequent  to  1781,  but  failing  to  satisfy  those  prior 
to  that  date.  A  consistent  result  could  be  obtained 
only  by  sacrificing  the  modern  or  the  ancient  ob- 
servations. "  I  have  thought  it  preferable,"  says  Bou- 
vard, "  to  abide  by  the  second  [alternative],  as  being 
that  which  combines  the  greater  number  of  proba- 
bilities in  favor  of  the  truth,  and  I  leave  it  to  the 
future  to  make  known  whether  the  difficulty  of  rec- 
onciling the  two  systems  result  from  the  inaccuracy 
of  ancient  observations,  or  whether  it  depend  upon 
some  extraneous  and  unknown  influence,  which  has 
acted  on  the  planet."  It  was  not  till  three  years  after 
the  death  of  Alexis  Bouvard  that  the  extraneous  in- 
fluence, of  which  he  thus  gave  in  1821  some  indica- 
tion, became  fully  known. 


186         THE  HISTORY  OF  SCIENCE 

Almost  immediately,  however,  after  the  publica- 
tion of  the  tables,  fresh  discrepancies  arose  between 
computation  and  observation.  At  the  first  meeting 
of  the  British  Association  in  1832  Professor  Airy 
in  a  paper  on  the  Progress  of  Astronomy  showed 
that  observational  data  in  reference  to  the  planet 
Uranus  diverged  widely  from  the  tables  of  1821. 
In  1833  through  his  influence  the  "  reduction  of  all 
the  planetary  observations  made  at  Greenwich  from 
1750 "  was  undertaken.  Airy  became  Astronomer 
Royal  in  1835,  and  continued  to  take  special  inter- 
est in  Uranus,  laying  particular  emphasis  on  the  fact 
that  the  radius  vector  assigned  in  the  tables  to  this 
planet  was  much  too  small. 

In  1834  the  Reverend  T.  J.  Hussey,  an  amateur 
astronomer,  had  written  to  Airy  in  reference  to  the 
irregularities  in  the  orbit  of  Uranus :  "  The  appar- 
ently inexplicable  discrepancies  between  the  ancient 
and  modern  observations  suggested  to  me  the  possi- 
bility of  some  disturbing  body  beyond  Uranus,  not 
taken  into  account  because  unknown.  ...  Subse- 
quently, in  conversation  with  Bouvard,  I  inquired  if 
the  above  might  not  be  the  case."  Bouvard  answered 
that  the  idea  had  occurred  to  him ;  indeed,  he  had 
had  some  correspondence  in  reference  to  it  in  1829 
with  Hansen,  an  authority  on  planetary  perturba- 
tions. 

In  the  following  year  Nicolai  (as  well  as  Valz) 
was  interested  in  the  problem  of  an  ultra-Uranian 
planet  in  connection  with  the  orbit  of  Halley's  comet 
(itself  the  subject  of  a  striking  scientific  prediction 
fulfilled  in  1758),  now  reappearing,  and  under  the 
disturbing  influence  of  Jupiter.  In  fact,  the  proba- 


SCIENTIFIC  PREDICTION  187 

bility  of  the  approaching  discovery  of  a  new  planet 
soon  found  expression  in  popular  treatises  on  astron- 
omy. Mrs.  Somerville  in  her  book  on  The  Connec- 
tion of  the  Physical  Sciences  (1836)  said  that  the 
discrepancies  in  the  records  of  Uranus  might  reveal 
the  existence  and  even  "  the  mass  and  orbit  of  a  body 
placed  for  ever  beyond  the  sphere  of  vision."  Simi- 
larly Madler  in  his  Popular  Astronomy  (1841) 
took  the  view  that  Uranus  might  have  been  pre- 
dicted by  study  of  the  perturbations  it  produced  in 
the  orbit  of  Saturn.  Applying  this  conclusion  to  a 
body  beyond  Uranus  we,  he  continued,  "  may,  in- 
deed, express  the  hope  that  analysis  will  one  day  or 
other  solemnize  this,  her  highest,  triumph,  making 
discoveries  with  the  mind's  eye  in  regions  where,  in 
our  actual  state,  we  are  unable  to  penetrate." 

One  should  not  pass  over  in  this  account  the  labors 
of  Eugene  Bouvard,  the  nephew  of  Alexis,  who  con- 
tinued to  note  anomalies  in  the  orbit  of  Uranus  and 
to  construct  new  planetary  tables  till  the  very  eve 
of  the  discovery  of  Neptune.  In  1837  he  wrote  to 
Airy  that  the  differences  between  the  observations 
of  Uranus  and  the  calculation  were  large  and  were 
becoming  continually  larger :  "  Is  that  owing  to  a 
perturbation  brought  about  in  this  planet  by  some 
body  situated  beyond  it?  I  don't  know,  but  that's 
my  uncle's  opinion." 

In  1840  the  distinguished  astronomer  Bessel  de- 
clared that  attempts  to  explain  the  discrepancies 
"  must  be  based  on  the  endeavor  to  discover  an  orbit 
and  a  mass  for  some  unknown  planet,  of  such  a  na- 
ture, that  the  resulting  perturbations  of  Uranus 
may  reconcile  the  present  want  of  harmony  in  the 


188         THE  HISTORY  OF  SCIENCE 

observations."  Two  years  later  he  undertook  re- 
searches in  reference  to  the  new  planet  of  whose  ex- 
istence he  felt  certain.  His  labors,  however,  were 
interrupted  by  the  death  of  his  assistant  Flemming, 
and  by  his  own  illness,  which  proved  fatal  in  1846, 
a  few  months  before  the  actual  discovery  of  Nep- 
tune. It  is  evident  that  the  quest  of  the  new  planet 
had  become  general.  The  error  of  Uranus  still 
amounted  to  less  than  two  minutes.  This  deviation 
from  the  computed  place  is  not  appreciable  by  the 
naked  eye,  yet  it  was  felt,  by  the  scientific  world,  to 
challenge  the  validity  of  the  Newtonian  theory,  or 
to  foreshadow  the  addition  of  still  another  planet  to 
our  solar  system. 

In  July,  1841,  John  Couch  Adams,  a  young  under- 
graduate of  St.  John's  College,  Cambridge,  whose 
interest  had  been  aroused  by  reading  Airy's  paper 
on  the  Progress  of  Astronomy,  made  note  of  his 
resolution  to  attempt,  after  completing  his  college 
course,  the  solution  of  the  problem  then  forming  in 
so  many  minds.  After  achieving  the  B.A.  as  senior 
wrangler  at  the  beginning  of  1843,  Adams  under- 
took to  "  find  the  most  probable  orbit  and  mass  of 
the  disturbing  body  which  has  acted  on  Uranus." 
The  ordinary  problem  in  planetary  perturbations 
calls  for  the  determination  of  the  effect  on  a  known 
orbit  exerted  by  a  body  of  known  mass  and  motion. 
This  was  an  inverse  problem  ;  the  perturbation  being 
given,  it  was  required  to  find  the  position,  mass,  and 
orbit  of  the  disturbing  planet.  The  data  were  fur- 
ther equivocal  in  that  the  elements  of  the  given 
planet  Uranus  were  themselves  in  doubt ;  the  unre- 
liability of  its  planetary  tables,  in  fact,  being  the 


SCIENTIFIC  PREDICTION  189 

occasion  of  the  investigation  now  undertaken.  That 
thirteen  unknown  quantities  were  involved  indicates 
sufficiently  the  difficulty  of  the  problem. 

Adams  started  with  the  assumptions,  not  improb- 
able, that  the  orbit  of  the  unknown  planet  was  a 
circle,  and  that  its  distance  from  the  sun  was  twice 
that  of  Uranus.  This  latter  assumption  was  in  accord 
with  the  so-called  "  Bode's  Law,"  which  taught  that 
a  simple  numerical  relationship  exists  between  the 
planetary  distances  (4,  7, 10, 16,  28,  52, 100,  196), 
and  that  the  planets  as  they  lie  more  remote  from 
the  sun  tend  to  be  more  nearly  double  the  distance 
of  the  next  preceding.  Adams  was  encouraged,  by 
his  first  attempt,  to  undertake  a  more  precise  de- 
termination. 

On  his  behalf  Professor  Challis  of  Cambridge  ap- 
plied to  Astronomer  Royal  Airy,  who  furnished  the 
Reductions  of  the  Planetary  Observations  made  at 
Greenwich  from  1750  till  1830.  In  his  second  en- 
deavor Adams  assumed  that  the  unknown  planet  had 
an  elliptical  orbit.  He  approached  the  solution  grad- 
ually, ever  taking  into  account  more  terms  of  the  per- 
turbations. In  September,  1845,  he  gave  the  results 
to  Challis,  who  wrote  to  Airy  on  the  22d  of  that 
month  that  Adams  sought  an  opportunity  to  submit 
the  solution  personally  to  the  Astronomer  Royal.  On 
the  21st  of  October,  1845,  the  young  mathematician, 
twice  disappointed  in  his  attempt  to  meet  Airy,  left 
at  the  Royal  Observatory  a  paper  containing  the 
elements  of  the  new  planet.  The  position  assigned 
to  it  was  within  about  one  degree  of  its  actual  place. 

On  November  5  Airy  wrote  to  Adams  and,  among 
other  things,  inquired  whether  the  solution  obtained 


190         THE  HISTORY  OF  SCIENCE 

would  account  for  the  errors  of  the  radius  vector  as 
well  as  for  those  of  heliocentric  longitude.  For  Airy 
this  was  a  crucial  question  ;  but  to  Adanis  it  seemed 
unessential,  and  he  failed  to  reply. 

By  this  time  a  formidable  rival  had  entered  the 
field.  Leverrier  at  the  request  of  Arago  had  un- 
dertaken to  investigate  the  irregularities  in  the 
tables  of  Uranus.  In  September  of  the  same  year 
Eugene  Bouvard  had  presented  new  tables  of  that 
planet.  Leverrier  acted  very  promptly  and  systemat- 
ically. His  first  paper  on  the  problem  undertaken 
appeared  in  the  Comptes  Rendus  of  the  Academie 
des  Sciences  November  10,  1845.  He  had  submit- 
ted to  rigorous  examination  the  data  in  reference 
to  the  disturbing  influence  of  Jupiter  and  of  Saturn 
on  the  orbit  of  Uranus.  In  his  second  paper,  June 
1,  1846,  Leverrier  reviewed  the  records  of  the  an- 
cient and  modern  observations  of  Uranus  (279  in 
all),  subjected  Bouvard's  tables  to  severe  criticism, 
and  decided  that  there  existed  in  the  orbit  of  Uranus 
anomalies  that  could  not  be  accounted  due  to  errors 
of  observation.  There  must  exist  some  extraneous 
influence,  hitherto  unknown  to  astronomers.  Some 
scientists  had  thought  that  the  law  of  gravitation 
did  not  hold  at  the  confines  of  the  solar  system 
(others  that  the  attractive  force  of  other  systems 
might  prove  a  factor),  but  Leverrier  rejected  this 
conception.  Other  theories  being  likewise  discarded 
he  asked :  "  Is  it  possible  that  the  irregularities  of 
Uranus  are  due  to  the  action  of  a  disturbing  planet, 
situated  in  the  ecliptic  at  a  mean  distance  double 
that  of  Uranus  ?  And  if  so,  at  what  point  is  this 
planet  situated?  What  is  its  mass?  What  are  the 


SCIENTIFIC  PREDICTION  191 

elements  of  the  orbit  which  it  describes  ?  "  The  con- 
clusion reached  by  the  calculations  recorded  in  this 
second  paper  was  that  all  the  so-called  anomalies  in 
the  observations  of  Uranus  could  be  explained  as  the 
perturbation  caused  by  a  planet  with  a  heliocentric 
longitude  of  252°  on  January  1,  1800.  This  would 
correspond  to  325°  January  1,  1847. 

Airy  received  Leverrier's  second  paper  on  June 
23,  and  was  struck  by  the  fact  that  the  French  mathe- 
matician assigned  the  same  place  to  the  new  planet 
as  had  Adams  in  the  preceding  October.  He  wrote 
to  Leverrier  in  reference  to  the  errors  of  the  radius 
vector  and  received  a  satisfactory  and  sufficiently 
compliant  reply.  At  one  time  the  Astronomer  Royal 
had  felt  very  skeptical  about  the  possibility  of  the 
discovery  which  his  own  labors  had  contributed  to 
advance.  He  had  always,  to  quote  his  own  rather 
nebulous  statement,  considered  the  correctness  of 
a  distant  mathematical  result  to  be  the  subject  of 
moral  rather  than  of  mathematical  evidence.  Now 
that  corroboration  of  Adams's  results  had  arrived, 
he  felt  it  urgent  to  make  a  telescopic  examination  of 
that  part  of  the  heavens  indicated  by  the  theoretical 
findings  of  Adams  and  Leverrier.  He  accordingly 
wrote  to  Professor  Challis,  July  9,  requesting  him 
to  employ  for  the  purpose  the  great  Northumberland 
equatorial  of  the  Cambridge  Observatory. 

Professor  Challis  had  felt,  to  use  his  own  language, 
that  it  was  so  novel  a  thing  to  undertake  observa- 
tions in  reliance  upon  merely  theoretical  deductions, 
that,  while  much  labor  was  certain,  success  appeared 
very  doubtful.  Nevertheless,  having  received  fresh 
instructions  from  Adams  relative  to  the  theoretical 


192         THE  HISTORY  OF  SCIENCE 

place  of  the  new  planet,  he  began  observations  July 
29.  On  August  4  in  fixing  certain  reference  points 
he  noted,  but  mistook  for  a  star,  the  new  planet.  On 
August  12,  having  directed  the  telescope  in  accord- 
ance with  Adams's  instructions  he  again  noted  the 
same  heavenly  body,  as  a  star.  Before  Challis  had 
compared  the  results  of  the  observation  of  August 
12  with  the  results  of  an  observation  of  the  same 
region  made  on  July  30,  and  arrived  at  the  inference 
that  the  body  in  question,  being  absent  in  the  latter 
observation,  was  not  a  star  but  a  planet,  the  prize  of 
discovery  had  fallen  into  the  hands  of  another  ob- 
server. 

On  August  31  had  appeared  Leverrier's  third 
paper,  in  which  were  stated  the  new  planet's  orbit, 
mass,  distance  from  the  sun,  eccentricity,  and  longi- 
tude. The  true  heliocentric  longitude  was  given  as 
326°  32'  for  January  1,  1847.  This  determination 
placed  the  planet  about  5°  to  the  east  of  star  8  of  Cap- 
ricorn. Leverrier  said  it  might  be  recognized  by  its 
disk,  which,  moreover,  would  subtend  a  certain  angle. 

The  systematic  and  conclusive  character  of  Lever- 
rier's research,  submitted  to  one  of  the  greatest  acad- 
emies of  science,  carried  conviction  to  the  minds  of 
astronomers.  The  learned  world  felt  itself  on  the  eve 
of  a  great  discovery.  Sir  John  Herschel,  in  an  ad- 
dress before  the  British  Association  on  September 
10,  said  that  the  year  past  had  given  prospect  of  a 
new  planet.  "  We  see  it  as  Columbus  saw  America 
from  the  shores  of  Spain.  Its  movements  have  been 
felt  trembling  along  the  far-reaching  line  of  our 
analysis  with  a  certainty  hardly  inferior  to  ocular 
demonstration." 


SCIENTIFIC  PREDICTION  193 

On  September  18  Leverrier  sent  a  letter  to  Dr. 
Galle,  of  the  Berlin  Observatory,  which  was  provided 
with  a  set  of  star  maps,  prepared  at  the  instance  of 
Bessel.  Galle  replied  one  week  later.  "  The  planet, 
of  the  position  of  which  you  gave  the  indication, 
really  exists.  The  same  day  that  I  received  your  let- 
ter [September  23]  I  found  a  star  of  the  eighth 
magnitude,  which  was  not  inscribed  in  the  excellent 
map  (prepared  by  Dr.  Bremiker)  belonging  to  the 
collection  of  star  maps  of  the  Royal  Academy  of 
Berlin.  The  observation  of  the  following  day  showed 
decisively  that  it  was  the  planet  sought."  It  was  only 
57'  from  the  point  predicted. 

Arago  said  that  the  discovery  made  by  Leverrier 
was  one  of  the  most  brilliant  manifestations  of  the 
precision  of  modern  astronomic  science.  It  would  en- 
courage the  best  geometers  to  seek  with  renewed  ardor 
the  eternal  truths  which,  in  Pliny's  phrase,  are  latent 
in  the  majesty  of  theory. 

Professor  Challis  received  Leverrier's  third  paper 
on  September  29,  and  in  the  evening  turned  his  mag- 
nificent refractor  to  the  part  of  the  heavens  that  Le- 
verrier had  so  definitely  and  so  confidently  indicated. 
Among  the  three  hundred  stars  observed  Challis  was 
struck  by  the  appearance  of  one  which  presented  a 
disk  and  shone  with  the  brightness  of  a  star  of  the 
eighth  magnitude.  This  proved  to  be  the  planet.  On 
October  1  Challis  heard  that  the  German  observer 
had  anticipated  him. 

Arago,  while  recognizing  the  excellent  work  done 
by  Adams  in  his  calculations,  thought  that  the  fact  that 
the  young  mathematician  had  failed  to  publish  his  re- 
sults should  deprive  him  of  any  share  whatever  in  the 


194         THE  HISTORY  OF  SCIENCE 

glory  of  the  discovery  of  the  new  planet,  and  that 
history  would  confirm  this  definite  judgment.  Arago 
named  the  new  planet  after  the  French  discoverer, 
but  soon  acquiesced  in  the  name  Neptune,  which  has 
since  prevailed. 

Airy,  in  whose  possession  Adams's  results  had  re- 
mained for  months  unpublished  and  unheeded,  wrote 
Leverrier:  "  You  are  to  be  recognized  beyond  doubt 
as  the  predictor  of  the  planet's  place."  A  vigorous 
official  himself,  Airy  was  deeply  impressed  by  the 
calm  decisiveness  and  definite  directions  of  the  French 
mathematician.  "  It  is  here,  if  I  mistake  not,  that  we 
see  a  character  far  superior  to  that  of  the  able,  or 
enterprising,  or  industrious  mathematician ;  it  is  here 
that  we  see  the  philosopher."  This  explains,  if  any- 
thing could,  his  view  that  a  distant  mathematical  re- 
sult is  the  subject  of  ethical  rather  than  of  mathe- 
matical evidence. 

Adams's  friends  felt  that  he  had  not  received  from 
either  of  the  astronomers,  to  whom  he  confided  his 
results,  the  kind  of  help  or  advice  he  should  have  re- 
ceived. Challis  was  kindly,  but  wanting  in  initiative. 
Although  he  had  command  of  the  great  Northumber- 
land telescope,  he  had  no  thought  of  commencing  the 
search  in  1845,  for,  without  mistrusting  the  evidence 
which  the  theory  gave  of  the  existence  of  the  planet, 
it  might  be  reasonable  to  suppose  that  its  position 
was  determined  but  roughly,  and  that  a  search  for  it 
must  necessarily  be  long  and  laborious.  In  the  view 
of  Simon  Newcomb,1  Adams's  results,  which  were 
delivered  at  the  Greenwich  Observatory  October  21, 
1845,  were  so  near  to  the  mark  that  a  few  hours' 
1  See  article  "  Neptune,"  Encyc.  Brit. 


SCIENTIFIC  PREDICTION  195 

close  search  could  not  have  failed  to  make  the  planet 
known. 

Both  Adams  and  Leverrier  had  assumed  as  a 
rough  approximation  at  starting  that  the  orbit  of  the 
new  planet  was  circular  and  that,  in  accordance  with 
Bode's  Law,  its  distance  was  twice  that  of  Uranus. 
S.  C.  Walker,  of  the  Smithsonian  Institution,  Wash- 
ington, was  able  to  determine  the  elements  of  the 
orbit  of  Neptune  accurately  in  1847.  In  February 
of  that  year  he  had  found  (as  had  Petersen  of  Al- 
tona  about  the  same  time)  that  Lalande  had  in  May, 
1795,  observed  Neptune  and  mistaken  it  for  a  fixed 
star.  When  Lalande's  records  in  Paris  were  studied, 
it  was  found  that  he  had  made  two  observations  of 
Neptune  on  May  8  and  10.  Their  failure  to  agree 
caused  the  observer  to  reject  one  and  mark  the  other 
as  doubtful.  Had  he  repeated  the  observation,  he 
might  have  noted  that  the  star  moved,  and  was  hi 
reality  a  planet. 

Neptune's  orbit  is  more  nearly  circular  than  that 
of  any  of  the  major  planets  except  Venus.  Its  dis- 
tance is  thirty  times  that  of  the  earth  from  the  sun 
instead  of  thirty-nine  times,  as  Bode's  Law  would 
require.  That  generalization  was  a  presupposition 
of  the  calculations  leading  to  the  discovery.  It  was 
then  rejected  like  a  discredited  ladder.  Man's  con- 
ception of  the  universe  is  widened  at  the  thought 
that  the  outmost  known  planet  of  our  solar  system 
is  about  2,796,000,000  miles  from  the  sun  and 
requires  about  165  years  for  one  revolution. 

Professor  Peirce,  of  Harvard  University,  point- 
ing to  the  difference  between  the  calculations  of 
Leverrier  and  the  facts,  put  forward  the  view  that 


196         THE  HISTORY  OF  SCIENCE 

the  discovery  made  by  Galle  must  be  regarded  as  a 
happy  accident.  This  view,  however,  has  not  been 
sustained. 


REFERENCES 

Sir  Robert  Ball,  Neptune's  Jubilee  Year,  Scientific  American, 

Supplement,  Oct.  10,  1896. 

Sir  Robert  Ball,  The  Story  of  the  Heavens,  chap.  xv. 
B.  A.  Gould,  Report  on  the  History  of  the  Discovery  of  Neptune, 

Smithsonian  Contributions  to  Knowledge,  1850. 
Robert  Grant,  History  of  Physical  Astronomy. 
Simon  Newcomb,  Popular  Astronomy. 
Benjamin  Peirce,  Proceedings  of  the  American  Academy  of  Arts 

and  Sciences,  vol.  i,  pp.  57-68,  144,  285,  338-41,  etc. 


CHAPTER  XV 

SCIENCE  AND  TRAVEL  THE  VOYAGE  OF  THE 

BEAGLE 

SIR  CHARLES  LYELL,  in  his  Principles  of  Ge- 
ology, the  first  edition  of  which  appeared  in  1830- 
1833,  says  :  "  If  it  be  true  that  delivery  be  the  first, 
second,  and  third  requisite  in  a  popular  orator,  it  is 
no  less  certain  that  travel  is  of  first,  second,  and 
third  importance  to  those  who  desire  to  originate 
just  and  comprehensive  views  concerning  the  struc- 
ture of  our  globe."  The  value  of  travel  to  science 
in  general  might  very  well  be  illustrated  by  Ly ell's 
own  career,  his  study  of  the  mountainous  regions  of 
France,  his  calculation  of  the  recession  of  Niagara 
Falls  and  of  the  sedimentary  deposits  of  the  Missis- 
sippi, his  observations  of  the  coal  formations  of  Nova 
Scotia,  and  of  the  composition  of  the  Great  Dismal 
Swamp  of  Virginia  —  suggestive  of  the  organic  origin 
of  the  carboniferous  rocks. 

Although  it  is  not  with  Lyell  that  we  have  here 
principally  to  deal,  it  is  not  irrelevant  to  say  that 
the  main  purpose  of  his  work  was  to  show  that  all 
past  changes  in  the  earth's  crust  are  referable  to 
causes  now  in  operation.  Differing  from  Hutton  as 
to  the  part  played  in  those  changes  by  subterranean 
heat,  Lyell  agreed  with  his  forerunner  in  ascribing 
geological  transformations  to  "the  slow  agency  of 
existing  causes."  He  was,  in  fact,  the  leader  of  the 
uniformitarians  and  opposed  those  geologists  who 


198         THE  HISTORY  OF  SCIENCE 

held  that  the  contemporary  state  of  the  earth's  crust 
was  owing  to  a  series  of  catastrophes,  stupendous 
exhibitions  of  natural  force  to  which  recent  history 
offered  no  parallel.  Also  enlightened  as  to  the  sig- 
nificance of  organic  remains  in  stratified  rock,  Lyell 
in  1830  felt  the  need  of  further  knowledge  in  refer- 
ence to  the  relation  of  the  plants  and  animals  rep- 
resented in  the  fossils  to  the  fauna  and  flora  now 


existing. 


It  is  to  Lyell's  disciple,  Charles  Darwin,  however, 
that  we  turn  for  our  main  illustration  of  the  value 
of  travel  for  comprehensive  scientific  generalization. 
Born,  like  another  great  liberator,  on  February  12, 
1809,  Darwin  was  only  twenty-two  years  old  when 
he  received  appointment  as  naturalist  on  H.M.S. 
Beagle,  about  to  sail  from  Devonport  on  a  voyage 
around  the  world.  The  main  purpose  of  the  expedi- 
tion, under  command  of  the  youthful  Captain  Fitz- 
roy,  three  or  four  years  older  than  Darwin,  was  to 
make  a  survey  of  certain  coasts  in  South  America 
and  the  Pacific  Islands,  and  to  carry  a  line  of  chron- 
ometrical  measurements  about  the  globe.  Looking 
back  in  1876  on  this  memorable  expedition,  the 
naturalist  wrote,  "The  voyage  of  the  Beagle  has 
been  by  far  the  most  important  event  in  my  life, 
and  has  determined  my  whole  career."  In  spite  of 
the  years  he  had  spent  at  school  and  college  he  re- 
garded this  experience  as  the  first  real  training  or 
education  of  his  mind. 

Darwin  had  studied  medicine  at  Edinburgh,  but 
found  surgery  distasteful.  He  moved  to  Cambridge, 
with  the  idea  of  becoming  a  clergyman  of  the  Estab- 
lished Church.  As  a  boy  he  had  attended  with  his 


SCIENCE  AND  TRAVEL  199 

mother,  daughter  of  Josiah  Wedgwood,  the  Unita- 
rian services.  At  Cambridge  he  graduated  without 
distinction  at  the  beginning  of  1831.  It  should  be 
said,  however,  that  the  traditional  studies  were  par- 
ticularly ill  suited  to  his  cast  of  mind,  that  he  had 
not  been  idle,  and  had  developed  particular  diligence 
in  different  branches  of  science,  and  above  all  as  a 
collector. 

He  was  six  feet  tall,  fond  of  shooting  and  hunt- 
ing, and  able  to  ride  seventy-five  or  eighty  miles 
without  tiring.  He  had  shown  himself  at  college 
fond  of  company,  and  a  little  extravagant.  He  was, 
though  a  sportsman,  extremely  humane  ;  had  a  hor- 
ror of  inflicting  pain,  and  such  repugnance  at  the 
thought  of  slavery  that  he  quarreled  violently  with 
Captain  Fitzroy  when  the  latter  condoned  the  abom- 
ination. Darwin  was  not,  however,  of  a  turbulent 
disposition.  Sir  James  Sulivan,  who  had  accompa- 
nied the  expedition  as  second  lieutenant,  said  many 
years  after :  "  I  can  confidently  express  my  belief 
that  during  the  five  years  in  the  Beagle,  he  was 
never  known  to  be  out  of  temper,  or  to  say  one  un- 
kind or  hasty  word  of  or  to  any  one." 

Darwin's  father  was  remarkable  for  his  powers 
of  observation,  while  the  grandfather,  Erasmus  Dar- 
win, is  well  known  for  his  tendency  to  speculation. 
Charles  Darwin  possessed  both  these  mental  charac- 
teristics in  an  eminent  degree.  One  who  has  con- 
versed with  him  reports  that  what  impressed  him 
most  in  meeting  the  great  naturalist  was  his  clear 
blue  eyes,  which  seemed  to  possess  almost  telescopic 
vision,  and  that  the  really  remarkable  thing  about 
Darwin  was  that  he  saw  more  than  other  people.  At 


200         THE  HISTORY  OF  SCIENCE 

the  same  time  it  will  scarcely  be  denied  that  his 
vision  was  as  much  marked  by  insight  as  by  careful 
observation,  that  his  reasoning  was  logical  and  sin- 
gularly tenacious,  and  his  imagination  vivid.  It  was 
before  this  supreme  seer  that  the  panorama  of  ter- 
restrial creation  was  displayed  during  a  five  years' 
voyage. 

No  one  can  read  Darwin's  Journal  descriptive  of 
the  voyage  of  the  Beagle  and  continue  to  entertain 
any  doubts  in  reference  to  his  aesthetic  sense  and 
poetic  appreciation  of  the  various  moods  of  nature. 
Throughout  the  voyage  the  scenery  was  for  him  the 
most  constant  and  highest  source  of  enjoyment.  His 
emotions  responded  to  the  glories  of  tropical  vegeta- 
tion in  the  Brazilian  forests,  and  to  the  sublimity  of 
Patagonian  wastes  and  the  forest-clad  hills  of  Tierra 
del  Fuego.  "  It  is  easy,"  writes  the  gifted  adoles- 
cent, "to  specify  the  individual  objects  of  admira- 
tion in  these  grand  scenes ;  but  it  is  not  possible  to 
give  an  adequate  idea  of  the  higher  feelings  of  won- 
der, astonishment,  and  devotion,  which  fill  and  ele- 
vate the  mind."  Similarly,  on  the  heights  of  the 
Andes,  listening  to  the  stones  borne  seaward  day 
and  night  by  the  mountain  torrents,  Darwin  re- 
marked :  "  The  sound  spoke  eloquently  to  the  geolo- 
gist ;  the  thousands  and  thousands  of  stones,  which 
striking  against  each  other,  made  the  one  dull  uni- 
form sound,  were  all  hurrying  in  one  direction.  It 
was  like  thinking  on  time,  where  the  minute  that 
now  glides  past  is  irrecoverable.  So  was  it  with 
these  stones,  the  ocean  is  their  eternity,  and  each 
note  of  that  wild  music  told  of  one  more  step  towards 
their  destiny." 


SCIENCE  AND  TRAVEL  201 

When  the  Beagle  left  Devonport,  December  27, 
1831,  the  young  naturalist  was  without  any  theory, 
and  when  the  ship  entered  Falmouth  harbor,  Octo- 
ber 2,  1836,  though  he  felt  the  need  of  a  theory  in 
reference  to  the  relations  of  the  various  species  of 
plants  and  animals,  he  had  not  formulated  one.  It 
was  not  till  1859  that  his  famous  work  on  the  Origin 
of  Species  appeared.  He  went  merely  as  a  collector, 
and  frequently  in  the  course  of  the  voyage  felt  a 
young  man's  misgivings  as  to  whether  his  collections 
would  be  of  value  to  his  Cambridge  professors  and 
other  mature  scientists. 

Professor  Henslow,  the  botanist,  through  whom 
Darwin  had  been  offered  the  opportunity  to  accom- 
pany the  expedition,  had  presented  his  pupil  with 
the  first  volume  of  Lyell's  Principles  of  Geology. 
(Perhaps,  after  Lyell,  the  most  potent  influence  on 
Darwin's  mind  at  this  time  was  that  of  Humboldt 
and  other  renowned  travelers,  whose  works  he  read 
with  avidity.)  At  the  Cape  Verde  Islands  he  made 
some  interesting  observations  of  a  white  calcareous 
stratum  which  ran  for  miles  along  the  coast  at  a 
height  of  about  forty-five  feet  above  the  water.  It 
rested  on  volcanic  rocks  and  was  itself  covered  with 
basalt,  that  is,  lava  which  had  crystallized  under  the 
sea.  It  was  evident  that  subsequently  to  the  forma- 
tion of  the  basalt  that  portion  of  the  coast  contain- 
ing the  white  stratum  had  been  elevated.  The  shells 
in  the  stratum  were  recent,  that  is,  corresponded  to 
those  still  to  be  found  on  the  neighboring  coast.  It 
occurred  to  Darwin  that  the  voyage  might  afford 
material  for  a  book  on  geology.  Later  in  the  voy- 
age, having  read  portions  of  his  Journal  to  Captain 


202        THE  HISTORY  OF  SCIENCE 

Fitzroy,  Darwin  was  encouraged  to  believe  that  this 
also  might  prove  worthy  of  publication. 

Darwin's  account  of  his  adventures  and  manifold 
observations  is  so  informal,  so  rich  in  detail,  as  not 
to  admit  of  summary.  His  eye  took  in  the  most  di- 
verse phenomena,  the  color  of  the  sea  or  of  rivers, 
clouds  of  butterflies  and  of  locusts,  the  cacique  with  his 
little  boy  clinging  to  the  side  of  a  horse  in  headlong 
flight,  the  great  earthquake  on  the  coast  of  Chile,  the 
endless  variety  of  plant  and  animal  life,  the  supersti- 
tion of  savage  and  padre,  the  charms  of  Tahiti,  the 
unconscious  humor  of  his  mountain  guides  for  whom 
at  an  altitude  of  eleven  thousand  feet  "  the  cursed 
pot  (which  was  a  new  one)  did  not  choose  to  boil 
potatoes "  —  all  found  response  in  Darwin's  open 
mind ;  everything  was  grist  to  his  mill.  Any  selec- 
tion from  the  richness  of  the  original  is  almost  sure 
to  show  a  tendency  not  obvious  in  the  Journal.  On 
the  other  hand,  it  is  just  such  multiplicity  of  phe- 
nomena as  the  Journal  mirrors  that  impels  every 
orderly  mind  to  seek  for  causes,  for  explanation. 
The  human  intellect  cannot  rest  till  law  gives  form 
to  the  wild  chaos  of  fact. 

No  disciple  of  Lyell  could  fail  to  be  convinced 
of  the  immeasurable  lapse  of  time  required  for  the 
formation  of  the  earth's  crust.  For  this  principle 
Darwin  found  abundant  evidence  during  the  years 
spent  in  South  America.  On  the  heights  of  the  Andes 
he  found  marine  shell  fossils  at  a  height  of  fourteen 
thousand  feet  above  sea-level.  That  such  an  eleva- 
tion of  submarine  strata  should  be  achieved  by  forces 
still  at  Nature's  command  might  well  test  the  faith 
of  the  most  ardent  disciple.  Of  how  great  those 


SCIENCE  AND  TRAVEL  203 

forces  are  Darwin  received  demonstration  on  the 
coast  of  Chile  in  1835.  Under  date  of  February  12, 
he  writes :  "  This  day  has  been  memorable  in  the 
annals  of  Valdivia  for  the  most  severe  earthquake 
experienced  by  the  oldest  inhabitant.  ...  A  bad 
earthquake  destroys  our  oldest  associations ;  the 
earth,  the  very  emblem  of  solidity,  has  moved  be- 
neath our  feet  like  a  thin  crust  over  a  fluid."  He 
observed  that  the  most  remarkable  effect  of  this 
earthquake  was  the  permanent  elevation  of  the  land. 
Around  the  Bay  of  Concepcion  it  was  raised  two  or 
three  feet,  while  at  the  island  of  Santa  Maria  the 
elevation  was  much  greater ;  "  on  one  part  Captain 
Fitzroy  found  beds  of  putrid  mussel  shells  still 
adhering  to  the  rocks,  ten  feet  above  high-water 
mark."  On  the  same  day  the  volcanoes  of  South 
America  were  active.  The  area  from  under  which 
volcanic  matter  was  actually  erupted  was  720  miles 
in  one  line  and  400  in  another  at  right  angles  to  it. 
Great  as  is  the  force  at  work,  ages  are  required  to 
produce  a  range  of  mountains  like  the  Cordilleras; 
moreover,  progress  is  not  uniform  and  subsidence 
may  alternate  with  elevation.  It  was  on  the  princi- 
ple of  the  gradual  subsidence  (and  elevation)  of  the 
bed  of  the  Pacific  Ocean  that  Darwin  accounted  for 
the  formation  of  coral  reefs.  Nothing  "is  so  unsta- 
ble as  the  level  of  the  crust  of  this  earth." 

Closely  associated  with  the  evidence  of  the  im- 
mensity of  the  force  of  volcanic  action  and  the  in- 
finitude of  time  elapsed,  Darwin  had  testimony  of 
the  multitude  of  plant  and  animal  species,  some  gi- 
gantic, others  almost  infinitely  small,  some  living, 
others  extinct.  We  know  that  his  thought  was  greatly 


204        THE  HISTORY  OF  SCIENCE 

affected  by  his  discovery  in  Uruguay  and  Patagonia 
of  the  fossil  remains  of  extinct  mammals,  all  the 
more  so  because  they  seemed  to  bear  relationship  to 
particular  living  species  and  at  the  same  time  to 
show  likeness  to  other  species.  The  Toxodon  (bow- 
tooth),  for  example,  was  a  gigantic  rodent  whose 
fossil  remains  were  discovered  in  the  same  region 
where  Darwin  found  living  the  capybara,  a  rodent 
as  large  as  a  pig ;  at  the  same  time  the  extinct  species 
showed  in  its  structure  certain  affinities  to  the  Eden- 
tata (sloths,  ant-eaters,  armadillos).  Other  fossils 
represented  gigantic  forms  distinctly  of  the  edentate 
order  and  comparable  to  the  Cape  ant-eater  and  the 
Great  Armadillo  (Dasypus  gig  as).  Again,  remains 
were  found  of  a  thick-skinned  non-ruminant  with 
certain  structural  likeness  to  the  Camelidae,  to  which 
the  living  species  of  South  American  ruminants,  the 
guanacos,  belong. 

Why  have  certain  species  ceased  to  exist  ?  As  the 
individual  sickens  and  dies,  so  certain  species  become 
rare  and  extinct.  Darwin  found  in  Northern  Pat- 
agonia evidence  of  the  Equus  curvidens,  an  extinct 
species  of  native  American  horse.  What  had  caused 
this  species  to  die  out?  Imported  horses  were  intro- 
duced at  Buenos  Ay  res  in  1537,  and  so  flourished 
in  the  wild  state  that  in  1580  they  were  found  as  far 
south  as  the  Strait  of  Magellan.  Darwin  was  well 
fitted  by  the  comprehensiveness  of  his  observations 
to  deal  with  the  various  factors  of  extinction  and 
survival.  He  studied  the  species  in  their  natural 
setting,  the  habitat,  and  range,  and  habits,  and  food 
of  the  different  varieties.  Traveling  for  three  years 
and  a  half  north  and  south  on  the  continent  of  South 


SCIENCE  AND  TRAVEL  205 

America,  he  noticed  one  species  replacing  another, 
perhaps  closely  allied,  species.  Of  the  carrion-feed- 
ing hawks  the  condor  has  an  immense  range,  but 
shows  a  predilection  for  perpendicular  cliffs.  If  an 
animal  die  on  the  plain  the  polyborus  has  preroga- 
tive of  feeding  first,  and  is  followed  by  the  turkey 
buzzard  and  the  gallinazo.  European  horses  and  cat- 
tle running  wild  in  the  Falkland  Islands  are  some- 
what modified  ;  the  horse  as  a  species  degenerating, 
the  cattle  increasing  in  size  and  tending  to  form 
varieties  of  different  color.  The  soil  being  soft  the 
hoofs  of  the  horse  grow  long  and  produce  lameness. 
Again,  on  the  mainland,  the  niata,  a  breed  of  cattle 
supposed  to  have  originated  among  the  Indians  south 
of  the  Plata,  are,  on  account  of  the  projection  of  the 
lower  jaw,  unable  to  browse  as  effectually  as  other 
breeds.  This  renders  them  liable  to  destruction  in 
times  of  drought.  A  similar  variation  in  structure 
had  characterized  a  species  of  extinct  ruminant  in 
India. 

How  disastrous  a  great  drought  might  prove  to 
the  cattle  of  the  Pampas  is  shown  by  the  records  of 
1825  and  of  1830.  So  little  rain  fell  that  there  was 
a  complete  failure  of  vegetation.  The  loss  of  cattle  in 
one  province  alone  was  estimated  at  one  million.  Of 
one  particular  herd  of  twenty  thousand  not  a  single 
one  survived.  Darwin  had  many  other  instances  of 
nature's  devastations.  After  the  Beagle  sailed  from 
the  Plata,  December  6,  1833,  vast  numbers  of  but- 
terflies were  seen  as  far  as  the  eye  could  range  in 
bands  of  countless  myriads.  "  Before  sunset  a  strong 
breeze  sprung  up  from  the  north,  and  this  must  have 
caused  tens  of  thousands  of  the  butterflies  and  other 


206        THE  HISTORY  OF  SCIENCE 

insects  to  perish."  Two  or  three  months  before  this 
he  had  ocular  proof  of  the  effect  of  a  hailstorm,  which 
in  a  very  limited  area  killed  twenty  deer,  fifteen 
ostriches,  numbers  of  ducks,  hawks,  and  partridges. 
In  the  war  of  extermination  that  was  ever  before 
the  great  naturalist's  eye  in  South  America,  what  is 
it  that  favors  a  species'  survival  or  determines  its 
extinction  ? 

Not  only  is  the  struggle  between  the  animals  and 
inanimate  nature,  the  plants  and  inanimate  nature, 
plant  and  animal,  rival  animals,  and  rival  plants ;  it 
goes  on  between  man  and  his  environment,  and,  very 
fiercely,  between  man  and  man.  Darwin  was  moved 
by  intense  indignation  at  the  slavery  on  the  east  coast 
and  the  cruel  oppression  of  the  laborer  on  the  west 
coast.  He  was  in  close  contact  with  the  sanguinary 
political  struggles  of  South  America,  and  with  a  war 
of  attempted  extermination  against  the  Indian.  He 
refers  to  the  shocking  but  "  unquestionable  fact,  that 
[in  the  latter  struggle]  all  the  women  who  appear 
above  twenty  years  old  are  massacred  in  cold  blood ! 
When  I  exclaimed  that  this  appeared  rather  inhu- 
man, he  [the  informant]  answered,  4  Why,  what  can 
be  done  ?  they  breed  so ! ' : 

In  all  his  travels  nothing  that  Darwin  beheld 
made  a  deeper  impression  on  his  sensitive  mind  than 
primitive  man.  "  Of  individual  objects,  perhaps  noth- 
ing is  more  certain  to  create  astonishment  than  the 
first  sight  in  his  native  haunt  of  a  barbarian  —  of 
man  in  his  lowest  and  most  savage  state.  One's  mind 
hurries  back  over  past  centuries,  and  then  asks,  could 
our  progenitors  have  been  men  like  these  ?  ...  I  do 
not  believe  it  is  possible  to  describe  or  paint  the  dif- 


SCIENCE  AND  TRAVEL  207 

ference  between  savage  and  civilized  man."  It  was 
at  Tierra  del  Fuego  that  he  was  particularly  shocked. 
He  admired  the  Tahitians ;  he  pitied  the  natives  of 
Tasmania,  corralled  like  wild  animals  and  forced  to 
migrate ;  he  thought  the  black  aborigines  of  Aus- 
tralia had  been  underestimated  and  remarked  with 
regret  that  their  numbers  were  decreasing  through 
their  association  with  civilized  man,  the  introduc- 
tion of  spirits,  the  increased  difficulty  of  procuring 
food,  and  contact  with  European  diseases.  In  this 
last  cause  tending  to  bring  about  extinction  there 
was  a  mysterious  element.  In  Chile  his  scientific 
acumen  had  been  baffled  in  the  attempt  to  explain  the 
invasion  of  the  strange  and  dreadful  disease  hydro- 
phobia. In  Australia  the  problem  of  the  transmission 
to  the  natives  of  various  diseases,  even  by  Europeans 
in  apparent  health,  confronted  his  intelligence.  "  The 
varieties  of  man  seem  to  act  on  each  other  in  the  same 
way  as  different  specimens  of  animals  —  the  stronger 
always  extirpating  the  weaker." 

It  was  at  Wollaston  Island,  near  Cape  Horn,  how- 
ever, that  Darwin  saw  savage  men  held  in  extremity 
by  the  hard  conditions  of  life,  and  at  bay.  They  had 
neither  food,  nor  shelter,  nor  clothing.  They  stood 
absolutely  naked  as  the  sleet  fell  on  them  and  melted. 
At  night,  "  naked  and  scarcely  protected  from  the 
wind  and  rain  of  this  tempestuous  climate,"  they  slept 
on  the  wet  ground  coiled  up  like  animals.  They  sub- 
sisted on  shell  fish,  putrid  whale's  blubber,  or  a  few 
tasteless  berries  and  fungi.  At  war,  the  different 
tribes  are  cannibals.  Darwin  writes,  "  It  is  certainly 
true,  that  when  pressed  in  winter  by  hunger,  they  kill 
and  devour  their  old  women  before  they  kill  their 


208        THE  HISTORY  OF  SCIENCE 

dogs."  A  native  boy,  when  asked  by  a  traveler  why 
they  do  this,  had  answered,  "  Doggies  catch  otters, 
old  women  no."  In  such  hard  conditions  what  are  the 
characteristics  that  would  determine  the  survival  of 
individual  or  tribe  ?  One  might  be  tempted  to  lay 
almost  exclusive  emphasis  on  physical  strength,  but 
Darwin  was  too  wise  ultimately  to  answer  thus  the 
question  that  for  six  or  seven  years  was  forming  in 
his  accurate  and  discriminating  mind. 

On  its  way  west  in  the  Pacific  the  Beagle  spent 
a  month  at  the  Galapagos  Archipelago,  which  lies 
under  the  equator  five  or  six  hundred  miles  from  the 
mainland.  "  Most  of  the  organic  productions  are  ab- 
original creations,  found  nowhere  else ;  there  is  even 
a  difference  between  the  inhabitants  of  the  different 
islands ;  yet  all  show  a  marked  relationship  with 
those  of  America."  Why  should  the  plants  and  ani- 
mals of  the  islands  resemble  tho«e  of  the  mainland, 
or  the  inhabitants  of  one  island  differ  from  those  of 
a  neighboring  island  ?  Darwin  had  always  held  that 
species  were  created  immutable,  and  that  it  was  im- 
possible for  one  species  to  give  rise  to  another. 

In  the  Galapagos  Archipelago  he  found  only  one 
species  of  terrestrial  mammal,  a  new  species  of  mouse, 
and  that  only  on  the  most  easterly  island  of  the  group. 
On  the  South  American  continent  there  were  at  least 
forty  species  of  mice,  those  east  of  the  Andes  being 
distinct  from  those  on  the  west  coast.  Of  land-birds 
he  obtained  twenty-six  kinds,  twenty-five  of  which 
were  to  be  found  nowhere  else.  Among  these,  a  hawk 
seemed  in  structure  intermediate  between  the  buzzard 
and  polyborus,  as  though  it  had  been  modified  and 
induced  to  take  over  the  functions  of  the  South  Ameri- 


SCIENCE  AND  TRAVEL  209 

can  carrion-hawk.  There  were  three  species  of  mock- 
ing-thrush,  two  of  them  confined  to  one  island  each. 
There  were  thirteen  species  of  finches,  all  peculiar  to 
the  archipelago.  In  the  different  species  of  geospiza 
there  is  a  perfect  gradation  in  the  size  of  the  beaks, 
only  to  be  appreciated  by  seeing  the  specimens  or 
their  illustrations. 

Few  of  the  birds  were  of  brilliant  coloration. 
The  same  was  true  of  the  plants  and  insects.  Darwin 
looked  in  vain  for  one  brilliant  flower.  This  was  in 
marked  contrast  to  the  fauna  and  flora  of  the  South 
American  tropics.  The  coloration  of  the  species  sug- 
gested comparison  with  that  of  the  plants  and  animals 
of  Patagonia.  Amid  brilliant  tropical  plants  brilliant 
plumage  may  afford  means  of  concealment,  as  well 
as  being  a  factor  in  the  securing  of  mates. 

Darwin  found  the  reptiles  the  most  striking  fea- 
ture of  the  zoology  of  the  islands.  They  seem  to  take 
the  place  of  the  herbivorous  mammalia.  The  huge 
tortoise  (Testudo  nigra)  native  in  the  archipelago 
is  so  heavy  as  to  be  lifted  only  by  six  or  eight  men. 
(The  young  naturalist  frequently  got  on  the  back  of 
a  tortoise,  but  as  it  moved  forward  under  his  encour- 
agement, he  found  it  very  difficult  to  keep  his  bal- 
ance.) Different  varieties,  if  not  species,  characterize 
the  different  islands.  Of  the  other  reptilia  should 
be  noted  two  species  of  lizard  of  a  genus  (Ambly- 
rhynchus)  confined  to  the  Galapagos  Islands.  One, 
aquatic,  a  yard  long,  fifteen  pounds  in  weight,  with 
"  limbs  and  strong  claws  admirably  adapted  for  crawl- 
ing over  the  rugged  and  fissured  masses  of  lava," 
feeds  on  seaweed.  When  frightened  it  instinctively 
shuns  the  water,  as  though  it  feared  especially  its 


210         THE  HISTORY  OF  SCIENCE 

aquatic  enemies.  The  terrestrial  species  is  confined  to 
the  central  part  of  the  group ;  it  is  smaller  than  the 
aquatic  species,  and  feeds  on  cactus,  leaves  of  trees, 
and  berries. 

Fifteen  new  species  of  sea-fish  were  obtained,  dis- 
tributed in  twelve  genera.  The  archipelago,  though 
not  rich  in  insects,  afforded  several  new  genera,  each 
island  with  its  distinct  kinds.  The  flora  of  the  Gala- 
pagos Islands  proved  equally  distinctive.  More  than 
half  of  the  flowering  plants  are  native,  and  the  species 
of  the  different  islands  show  wonderful  differences. 
For  example,  of  seventy-one  species  found  on  James 
Island  thirty-eight  are  confined  to  the  archipelago 
and  thirty  to  this  one  island. 

In  October  the  Beagle  sailed  west  to  Tahiti,  New 
Zealand,  Australia,  Keeling  or  Cocos  Islands,  Mau- 
ritius, St.  Helena,  Ascension ;  arrived  at  Bahia,  Brazil, 
August  1,  1836  ;  and  finally  proceeded  from  Brazil 
to  England.  Among  his  many  observations,  Darwin 
noted  the  peculiar  animals  of  Australia,  the  kanga- 
roo-rat, and  "several  of  the  famous  Ornithorhyn- 
cJius  paradoxus"  or  duckbill.  On  the  Keeling  or 
Cocos  Islands  the  chief  vegetable  production  is  the 
cocoanut.  Here  Darwin  observed  crabs  of  monstrous 
size,  with  a  structure  which  enabled  them  to  open 
the  cocoanuts.  They  thus  secured  their  food,  and 
accumulated  "surprising  quantities  of  the  picked 
fibres  of  the  cocoanut  husk,  on  which  they  rest  as  a 
bed." 

In  preparing  his  Journal  for  publication  in  the 
autumn  of  1836  the  young  naturalist  saw  how  many 
facts  pointed  to  the  common  descent  of  species.  He 
thought  that  by  collecting  all  facts  that  bore  on  the 


SCIENCE  AND  TRAVEL  211 

variation  of  plants  and  animals,  wild  or  domesticated, 
light  might  be  thrown  on  the  whole  subject.  "  I 
worked  on  true  Baconian  principles,  and,  without 
any  theory,  collected  facts  on  a  wholesale  scale."  He 
saw  that  pigeon-fanciers  and  stock-breeders  develop 
certain  types  by  preserving  those  variations  that  have 
the  desired  characteristics.  This  is  a  process  of  arti- 
ficial selection.  How  is  selection  made  by  Nature  ? 

In  1838  he  read  Malthus'  Essay  on  the  Prin- 
ciple of  Population,  which  showed  how  great  and 
rapid,  without  checks  like  war  and  disease,  the  in- 
crease in  number  of  the  human  race  would  be.  He 
had  seen  something  in  his  travels  of  rivalry  for 
the  means  of  subsistence.  He  now  perceived  "  that 
under  these  circumstances  favorable  variations  would 
tend  to  be  preserved,  and  unfavorable  ones  to  be  de- 
stroyed. The  results  of  this  would  be  the  formation 
of  a  new  species."  As  special  breeds  are  developed  by 
artificial  selection,  so  new  species  evolve  by  a  process 
of  natural  selection.  Those  genera  survive  which  give 
rise  to  species  adapted  to  new  conditions  of  exist- 
ence. 

In  1858,  before  Darwin  had  published  his  theory, 
lie  received  from  another  great  traveler,  Alfred 
Russel  Wallace,  then  at  Ternate  in  the  Moluccas,  a 
manuscript  essay,  setting  forth  an  almost  identical 
view  of  the  development  of  new  species  through  the 
survival  of  the  fittest  in  the  struggle  for  existence. 


THE  HISTORY  OF  SCIENCE 


REFERENCES 

Charles  Darwin,  A  Naturalist's  Journal. 

Francis  Darwin,  The  Life  and  Letters  of  Charles  Darwin. 

W.  A.  Locy,  Biology  and  its  Makers  (third  revised  edition), 

chap.  xix. 

G.  J.  Romanes,  Darvrin  and  After  Darvrin,  vol.  I. 
A.  R.  Wallace,  Darwinism. 
See  also  John  W.  Judd,  The  Coming  of  Evolution  (The  Cambridge 

Manuals  of  Science  and  Literature). 


CHAPTER  XVI 

SCIENCE    AND    WAR PASTEUR,    LISTER 

IN  the  history  of  science  war  is  no  mere  interruption, 
but  a  great  stimulating  influence,  promoting  directly 
or  indirectly  the  liberties  of  the  people,  calling  into 
play  the  energy  of  artisan  and  manufacturer,  and  in- 
creasing the  demand  for  useful  and  practical  studies. 
In  the  activities  of  naval  and  military  equipment  and 
organization  this  influence  is  obvious  enough;  it  is 
no  less  real  in  the  reaction  from  war  which  impels 
all  to  turn  with  new  zest  to  the  arts  and  industries 
of  peace  and  to  cherish  whatever  may  tend  to  culture 
and  civil  progress.  Not  infrequently  war  gives  rise, 
not  only  to  new  educational  ideals,  but  to  new  insti- 
tutions and  to  new  types  of  institution  favorable 
to  the  advancement  of  science.  As  we  have  already 
seen,  the  Royal  Society  and  Milton's  Academies  owed 
their  origin  to  the  Great  Rebellion.  Similarly  the 
Ecole  Polytechnique,  mother  of  many  scientific  dis- 
coveries, rose  in  answer  to  the  needs  of  the  French 
Revolution.  No  less  noteworthy  was  the  reconstruction 
of  education  under  the  practical  genius  of  Napoleon 
I,  the  division  of  France  into  academies,  the  found- 
ing of  the  lycees,  the  reestablishment  of  the  great 
Ecole  Norrnale,  and  the  organization  of  the  Imperial 
University  with  new  science  courses  and  new  pro- 
vincial Faculties  at  Rennes,  Lille,  and  elsewhere. 
With  all  these  different  forms  in  which  the  influence 
of  war  makes  itself  felt  in  the  progress  of  science 


214         THE  HISTORY  OF  SCIENCE 

the  life  and  career  of  Louis  Pasteur  (1822-1895),  the 
founder  of  bacteriology,  stood  intimately  associated. 

He  was  born  at  Dole,  but  the  family  a  few  years 
later  settled  at  Arbois.  For  three  generations  the 
Pasteurs  had  been  tanners  in  the  Jura,  and  they 
naturally  adhered  to  that  portion  of  the  population 
which  hailed  the  Revolution  as  a  deliverance.  The 
great-grandfather  was  the  first  freeman  of  Pasteur's 
forbears,  having  purchased  with  money  his  emanci- 
pation from  serfdom.  The  father  in  1811,  at  the  age 
of  twenty,  was  one  of  Napoleon's  conscripts,  and  in 
1814  received  from  the  Emperor,  for  valor  and  fidel- 
ity, the  Cross  of  the  Legion  of  Honor.  The  direct- 
ness and  endurance  of  the  influence  of  this  trained 
veteran  on  his  gifted  son  a  hundred  fine  incidents 
attest.  In  1848  —  year  of  revolt  in  the  monarchies 
of  Europe  —  the  young  scientist  enrolled  himself  in 
the  National  Guard,  and,  seeing  one  day  in  the  Place 
du  Pantheon  a  structure  inscribed  with  the  words 
autel  de  la  patrie,  he  placed  upon  it  all  the  humble 
means — one  hundred  and  fifty  francs  —  then  at  his 
disposal. 

It  was  in  that  same  year  that  Pasteur  put  on 
record  his  discovery  of  the  nature  of  racemic  acid, 
his  first  great  service  to  science,  from  which  all  his 
other  services  were  to  proceed.  As  a  boy  he  had  at- 
tended the  college  at  Arbois  where  his  teacher  had  in- 
spired him  with  an  ambition  to  enter  the  great  Ecole 
Normale.  Before  reaching  that  goal  he  took  his  bache- 
lor's degree  in  science  as  well  as  in  arts  at  the  Bes- 
an^on  college.  At  Paris  he  came  in  contact  with  the 
leaders  of  the  scientific  world — Claude  Bernard, 
Balard,  Dumas,  Biot. 


SCIENCE  AND  WAR  215 

J.  B.  Biot  had  entered  the  ranks  of  science  by  way 
of  the  Ecole  Polytechnique  and  the  artillery  service. 
In  1819  he  had  announced  that  the  plane  of  polar- 
ized light  —  for  example,  a  ray  passed  through  Ice- 
land spar  —  is  deflected  to  right  or  left  by  various 
chemical  substances.  Among  these  is  common  tartaric 
acid  —  the  acid  of  grape-juice,  obtained  from  wine 
lees.  Racemic  acid,  however,  which  is  identical  with 
tartaric  acid  in  its  chemical  constituents,  is  optically 
inactive,  rotating  the  plane  of  polarized  light  neither 
to  the  right  nor  the  left.  This  substance  Pasteur 
subjected  to  special  investigation.  He  scrutinized 
the  crystals  of  sodium  ammonium  racemate  obtained 
from  aqueous  solution.  These  he  observed  to  be  of 
two  kinds  differing  in  form  as  a  right  glove  from  a 
left,  or  as  an  object  from  its  mirror-image.  Separat- 
ing the  crystals  according  to  the  difference  of  form, 
he  made  a  solution  from  each  group.  One  solution, 
tested  in  the  polarized-light  apparatus,  turned  the 
plane  to  the  right;  the  other  solution  turned  it  to  the 
left.  He  had  made  a  capital  discovery  of  far-reaching 
importance,  namely,  that  racemic  acid  is  composite, 
consisting  of  dextro-tartaric  and  laevo-tartaric  acids. 
Biot  hesitated  to  credit  a  mere  tyro  with  such  an 
achievement.  The  experiment  was  repeated  in  his 
presence.  Convinced  by  ocular  demonstration,  he 
was  almost  overcome  with  emotion.  "  My  dear  boy," 
he  exclaimed,  "I  have  loved  the  sciences  so  much 
my  life  through  that  that  makes  my  heart  jump." 

Pasteur  began  his  regular  professional  experience 
as  a  teacher  of  physics  in  the  Dijon  lycee,  but  he  was 
soon  transferred  to  the  University  t>f  Strasburg 
(1849).  There  he  married  the  daughter  of  the 


216         THE  HISTORY  OF  SCIENCE 

rector  of  the  academic,  and  three  years  later  became 
Professor  of  Chemistry.  In  1854  he  was  appointed 
Dean  of  the  Faculty  of  Sciences  at  Lille,  a  town 
then  officially  described  as  the  richest  center  of  in- 
dustrial activity  in  the  north  of  France.  In  his  open- 
ing address  he  showed  the  value  and  attractiveness 
of  practical  studies.  He  believed  as  an  educator  in 
the  close  alliance  of  laboratory  and  factory.  Appli- 
cation should  always  be  the  aim,  but  resting  on  the 
severe  and  solid  basis  of  scientific  principles ;  for  it 
is  theory  alone  which  can  bring  forth  and  develop 
the  spirit  of  invention. 

His  own  study  of  racemic  acid,  begun  in  the  labo- 
ratories of  Paris,  and  followed  up  in  the  factories  of 
Leipzig,  Prag,  and  Vienna,  had  led  to  his  theory  of 
molecular  dissymmetry,  the  starting  point  of  modern 
stereo-chemistry.  It  now  gave  rise  on  Pasteur's  part 
to  new  studies  and  to  new  applications  to  the  indus- 
tries. He  tried  an  experiment  which  seems  almost 
whimsical,  placing  ammonium  racemate  in  the  ordi- 
nary conditions  of  fermentation,  and  observed  that 
only  one  part  —  the  dextro-rotatory  —  ferments  or 
putrefies.  Why  ?  "  Because  the  ferments  of  that  fer- 
mentation feed  more  easily  on  the  right  hand  than 
on  the  left  hand  molecules. "  He  succeeded  in  keep- 
ing alive  one  of  the  commonest  moulds  on  the  sur- 
face of  ashes  and  racemic  acid,  and  saw  the  laevo- 
tartaric  acid  appear.  It  was  thus  that  he  passed  from 
the  study  of  crystals  to  the  study  of  ferments. 

In  the  middle  of  the  nineteenth  century  little  was 
known  of  the  nature  of  fermentation,  though  some 
sought  to  explain  by  this  ill-understood  process  the 
origin  of  various  diseases  and  of  putrefaction.  Why 


SCIENCE  AND  WAR  217 

does  fruit-juice  produce  alcohol,  wine  turn  to  vin- 
egar, milk  become  sour,  and  butter  rancid?  Pas- 
teur's interest  in  these  problems  of  fermentation  was 
stimulated  by  one  of  the  industries  of  Lille.  He  was 
accustomed  to  visit  with  his  students  the  factories  of 
that  place  as  well  as  those  of  neighboring  French 
and  Belgian  cities.  The  father  of  one  of  his  students 
was  engaged  in  the  manufacture  of  alcohol  from  beet- 
root sugar,  and  Pasteur  came  to  be  consulted  when 
difficulties  arose  in  the  manufacturing  process.  He 
discovered  a  relationship  between  the  development  of 
the  yeast  and  the  success  or  failure  of  the  fermenta- 
tion, the  yeast  globules  as  seen  under  the  microscope 
showing  an  alteration  of  form  when  the  fermentation 
was  not  proceeding  satisfactorily.  In  1857  Pasteur 
on  the  basis  of  this  study  was  able  to  demonstrate 
that  alcoholic  fermentation,  that  is,  the  conversion 
of  sugar  into  alcohol,  carbonic  acid,  and  other  com- 
pounds, depends  on  the  action  of  yeast,  the  cells  of 
which  are  widely  disseminated  in  the  atmosphere. 

In  this  year  of  his  second  great  triumph  Pasteur 
was  appointed  director  of  science  studies  in  the  Ecole 
Normale,  from  which  he  had  graduated  in  1847. 
Two  years  later  the  loss  of  his  daughter  by  a  com- 
municable disease — typhoid  fever  —  had  a  great 
effect  on  his  sensitive  and  profound  mind.  Many  of 
his  opponents,  it  is  true,  found  Pasteur  implacable 
in  controversy.  Undoubtedly  he  had  the  courage  of 
his  convictions,  and  his  belief  that,  for  the  sake  of 
human  welfare,  right  views  —  his  views  won  by  tire- 
less experiment  —  must  prevail,  gained  him  the  name 
of  a  fighter.  But  in  all  the  intimate  relations  of  life 
his  essential  tenderness  was  manifest.  Like  Darwin 


218         THE  HISTORY  OF  SCIENCE 

he  had  a  horror  of  inflicting  pain,  and  always  in- 
sisted, when  operations  on  animals  were  necessary 
in  the  laboratory,  on  the  use  of  anaesthetics  (our 
command  of  which  had  been  greatly  advanced  by 
Simpson  in  1847).  Emile  Koux  said  that  Pasteur's 
agitation  at  witnessing  the  slightest  exhibition  of 
pain  would  have  been  ludicrous  if,  in  so  great  a  man, 
it  had  not  been  touching. 

A  few  months  after  his  daughter's  death  Pasteur 
wrote  to  one  of  his  friends :  "  I  am  pursuing  as  best 
I  can  these  studies  on  fermentation,  which  are  of 
great  interest,  connected  as  they  are  with  the  im- 
penetrable mystery  of  life  and  death.  I  am  hoping 
to  make  a  decisive  advance  very  soon,  by  solving 
without  the  least  lack  of  clearness  the  famous  ques- 
tion of  spontaneous  generation."  Two  years  previ- 
ously a  scientist  had  claimed  that  animals  and  plants 
could  be  generated  in  a  medium  of  artificial  air  or 
oxygen,  from  which  all  atmospheric  air  and  all  germs 
of  organized  bodies  had  been  precluded.  Pasteur 
now  filtered  atmospheric  air  through  a  plug  of  cot- 
ton or  asbestos  (a  procedure  which  had  been  fol- 
lowed by  others  in  1854),  and  proved  that  in  air 
thus  treated  no  fermentation  takes  place.  Nothing 
in  the  atmosphere  causes  life  except  the  micro-organ- 
isms it  contains.  He  even  demonstrated  that  a  pu- 
trescible  fluid  like  blood  will  remain  unchanged  in 
an  open  vessel  so  constructed  as  to  exclude  atmos- 
pheric dust. 

Pasteur's  critics  maintained  that  if  putrefaction 
and  fermentation  be  caused  solely  by  microscopic 
organisms,  then  these  must  be  found  everywhere  and 
in  such  quantities  as  to  encumber  the  air.  He  replied 


SCIENCE  AND  WAR  219 

that  they  were  less  numerous  in  some  parts  of  the 
atmosphere  than  in  others.  To  prove  his  contention 
he  set  out  for  Arbois  with  a  large  number  of  glass 
bulbs  each  half  filled  with  a  putrescible  liquid.  The 
necks  of  the  bulbs  had  been  drawn  out  and  hermet- 
ically sealed  after  the  contents  had  been  boiled.  In 
case  the  necks  were  broken  (to  be  again  sealed  im- 
mediately), the  air  would  rush  in,  and  (if  it  held 
the  requisite  micro-organisms)  furnish  the  condi- 
tions for  putrefaction.  It  was  found  that  in  every 
trial  the  contents  of  a  certain  number  of  the  bulbs 
always  escaped  alteration.  Twenty  were  opened  in 
the  country  near  Arbois  free  from  human  habita- 
tions. Eight  out  of  the  twenty  showed  signs  of  pu- 
trefaction. Twenty  were  exposed  to  the  air  on  the 
heights  of  the  Jura  at  an  altitude  of  eight  hundred 
and  fifty  meters  above  sea-level ;  the  contents  of  five 
of  these  subsequently  putrefied.  Twenty  others  were 
opened  near  Mont  Blanc  at  an  altitude  of  two  thou- 
sand meters  and  while  a  wind  was  blowing  from  the 
Mer  de  Glace ;  in  this  case  the  contents  of  only  one 
of  the  bulbs  became  putrefied. 

While  his  opponents  still  professed  to  believe  in 
the  creation  of  organized  beings  lacking  parents, 
Pasteur  was  under  the  influence  of  the  theory  of 
"the  slow  and  progressive  transformation  of  one 
species  into  another,"  and  was  becoming  aware  of 
phases  of  the  struggle  for  existence  hitherto  shrouded 
in  mystery.  He  wished  he  said  to  push  these  studies 
far  enough  to  prepare  the  way  for  a  serious  investi- 
gation of  the  origin  of  disease. 

He  returned  to  the  study  of  lactic  fermentation, 
showed  that  butyric  fermentation  may  be  caused  by 


220         THE  HISTORY  OF  SCIENCE 

organisms  which  live  in  the  absence  of  oxygen,  while 
vinegar  is  produced  from  wine  through  the  agency 
of  bacteria  freely  supplied  with  the  oxygen  of  the 
air.  Pasteur  was  seeing  ever  more  clearly  the  part 
played  by  the  infkiitesimally  small  in  the  economy 
of  nature.  Without  these  microscopic  beings  life 
would  become  impossible,  because  death  would  be 
incomplete.  On  the  basis  of  Pasteur's  study  of  fer- 
mentation, his  demonstration  that  decomposition  is 
owing  to  living  organisms  and  that  minute  forms  of 
life  spring  from  parents  like  themselves,  his  disciple 
Joseph  Lister  began  in  1864  to  develop  antiseptic 
surgery. 

Pasteur's  attention  was  next  directed  to  the  wine 
industry,  which  then  had  an  annual  value  to  France 
of  500,000,000  francs.  Might  not  the  acidity,  bit- 
terness, defective  flavor,  which  were  threatening  the 
foreign  sale  of  French  wines,  be  owing  to  ferments  ? 
He  discovered  that  this  was,  indeed,  the  case,  and 
that  the  diseases  of  wine  could  be  cured  by  the  sim- 
ple expedient  of  heating  the  liquor  for  a  few  mo- 
ments to  a  temperature  of  50°  to  60°  C.  Tests  on  a 
considerable  scale  were  made  by  order  of  the  naval 
authorities.  The  ship  Jean  Bart  before  starting  on 
a  voyage  took  on  board  five  hundred  liters  of  wine, 
half  of  which  had  been  heated  under  Pasteur's  direc- 
tions. At  the  end  of  ten  months  the  pasteurized 
wine  was  mellow  and  of  good  color,  while  the  wine 
which  had  not  been  heated  had  an  astringent,  almost 
bitter,  taste.  A  more  extensive  test  —  seven  hundred 
hectoliters,  of  which  six  hundred  and  fifty  had  been 
pasteurized  —  was  carried  out  on  the  frigate  la 
Sibylle  with  satisfactory  results.  Previously  wines 


SCIENCE  AND  WAR  221 

had  been  preserved  by  the  addition  of  alcohol,  which 
made  them  both  dearer  and  more  detrimental  to 
health. 

In  1865  Pasteur  was  called  upon  to  exercise  his 
scientific  acumen  on  behalf  of  the  silk  industry.  A 
disease — pebrine  —  had  appeared  among  silkworms 
in  1845.  In  1849  the  effect  on  the  French  industry 
was  disastrous.  In  the  single  arrondissement  of 
Alais  an  annual  income  of  120,000,000  francs  was 
lost  for  the  subsequent  fifteen  years.  The  mulberry 
plantations  of  the  Cevennes  were  abandoned  and  the 
whole  region  was  desolate.  Pasteur,  at  the  instiga- 
tion of  the  Minister  of  Agriculture,  undertook  an 
investigation.  After  four  or  five  years,  in  spite  of 
repeated  domestic  afflictions  and  the  breakdown  of 
his  own  health,  he  arrived  at  a  successful  conclu- 
sion. Pebrine,  due  to  "  corpuscles  "  readily  detected 
under  the  microscope,  could  be  recognized  at  the  mo- 
ment of  the  moth's  formation.  A  second  disease, 
flacherie^  was  due  to  a  micro-organism  found  in  the 
digestive  cavity  of  the  moth.  Measures  were  taken 
to  select  the  seed  of  the  healthy  moths  and  to  destroy 
the  others.  These  investigations  revealed  the  infini- 
tesiinally  small  as  disorganizes  of  living  tissue,  and 
brought  Pasteur  nearer  his  purpose  "  of  arriving," 
as  he  had  expressed  it  to  Napoleon  III  in  1863,  "at 
the  knowledge  of  the  causes  of  putrid  and  contagious 
diseases." 

Returning  in  July,  1870,  from  a  visit  to  Liebig 
at  Munich,  Pasteur  heard  at  Strasburg  of  the  im- 
minence of  war.  All  his  dreams  of  conquest  over 
disease  and  death  seemed  to  vanish.  He  hurried  to 
Paris.  His  son,  eighteen  years  of  age,  set  out  with 


222         THE  HISTORY  OF  SCIENCE 

the  army.  Every  student  of  the  Ecole  Normale  en- 
listed. Pasteur's  laboratory  was  used  to  house  sol- 
diers. He  himself  wished  to  be  enrolled  in  the  Na- 
tional Guard,  and  had  to  be  told  that  a  half -paralyzed 
man  could  not  render  military  service.  He  was  ob- 
sessed with  horror  of  wanton  bloodshed  and  with 
indignation  at  the  insolence  of  armed  injustice. 
Trained  to  serve  his  country  only  in  one  way  he 
tried,  but  in  vain,  to  resume  his  researches.  He  re- 
tired to  the  old  home  town  of  Arbois,  and  sought  to 
distract  his  mind  from  the  contemplation  of  human 
baseness.  Arbois  was  entered  by  the  enemy  in  Janu- 
ary with  the  usual  atrocities  of  war.  Pasteur  accom- 
panied by  wife  and  daughter  had  gone  in  search  of  his 
son,  sick  at  Pontarlier.  The  boy  was  restored  to  health 
and  returned  to  his  regiment  the  following  month. 

During  this  crisis  Pasteur  and  his  friends  felt,  as 
many  English  scientists  feel  in  1917,  in  reference 
to  ignorance  in  high  places.  "We  are  paying  the 
penalty,"  he  said,  "  of  fifty  years'  forgetf ulness  of 
science,  and  of  its  conditions  of  development."  Again 
he  speaks,  as  Englishmen  to-day  very  well  might,  of 
the  neglect,  disdain  even,  of  the  country  for  great 
intellectual  men,  especially  in  the  realm  of  exact  sci- 
ence. In  the  same  strain  his  friend  Bertin  said  that 
after  the  war  everything  would  have  to  be  rebuilt 
from  the  top  to  the  bottom,  the  top  especially.  Pas- 
teur recalled  the  period  of  1792  when  Lavoisier, 
Berthollet,  Monge,  Fourcroy,  Guyton  de  Morveau, 
Chaptal,  Clouet,  and  other  scientists  had  furnished 
France  with  gunpowder,  steel,  cannon,  fortifications, 
balloons,  leather,  and  other  means  to  repel  unjust 
invasion. 


SCIENCE  AND  WAR  223 

On  the  day  after  Sedan  the  Quaker  surgeon  Lister 
had  published  directions  for  the  use  of  aqueous  solu- 
tions of  carbolic  acid  to  destroy  septic  particles  in 
wounds,  and  of  oily  solutions  "to  prevent  putrefac- 
tive fermentation  from  without."  He  recognized  that 
the  earlier  the  case  comes  from  the  field  the  greater 
the  prospect  of  success.  Sedillot  (the  originator 
of  the  term  " microbe"),  at  the  head  of  an  ambulance 
corps  in  Alsace,  was  a  pioneer  in  the  rapid  transport 
of  wounded  from  the  field  of  battle.  He  knew  the 
horrors  of  purulent  infection  in  military  hospitals, 
and  regretted  that  the  principles  of  Pasteur  and 
Lister  were  not  more  fully  applied. 

After  the  war  was  over,  Pasteur  kept  repeating 
his  life-long  exhortation  :  We  must  work  —  "  Tra- 
vaillez,  travaillez  toujours  I "  He  applied  himself  to 
a  study  of  the  brewing  industry.  He  did  not  believe 
in  spontaneous  alterations,  but  found  that  every 
marked  change  in  the  quality  of  beer  coincides 
with  the  development  of  micro-organisms.  He  was 
able  to  tell  the  English  brewers  the  defects  in  their 
output  by  a  microscopic  examination  of  their  yeast. 
("Wre  must  make  some  friends  for  our  beloved 
France,"  he  said.)  Bottled  beer  could  be  pasteur- 
ized by  bringing  it  to  a  temperature  of  50°  to  55°  C. 
Whenever  beer  contains  no  ferments  it  is  unaltera- 
ble. His  scrupulous  mind  was  coming  ever  closer  to 
the  goal  of  his  ambition.  This  study  of  the  diseases 
of  beer  led  him  nearer  to  a  knowledge  of  infections. 
Many  micro-organisms  may,  must,  be  detrimental  to 
the  health  of  man  and  animals. 

In  1874  the  Government  conferred  upon  Pasteur 
a  life  annuity  of  twelve  thousand  francs,  an  equiva- 


224         THE  HISTORY  OF  SCIENCE 

lent  of  his  salary  as  Professor  of  Chemistry  at  the 
Sorbonne.  (He  had  received  appointment  in  1867, 
but  had  been  compelled  by  ill-health  to  relinquish 
his  academic  functions.)  The  grant  was  in  all  re- 
spects wise.  Huxley  remarked  that  Pasteur's  discov- 
eries alone  would  suffice  to  cover  the  war  indemnity 
of  five  milliards  paid  by  France  to  Germany  in  1871. 
Moreover,  all  his  activities  were  dictated  by  patriotic 
motives.  He  felt  that  science  is  of  no  country  and 
that  its  conquests  belong  to  mankind,  but  that  the 
scientist  must  be  a  patriot  in  the  service  of  his  native 
land. 

Pasteur  now  applied  his  energies  to  the  study  of 
virulent  diseases,  following  the  principles  of  his  ear- 
lier investigations.  He  opposed  those  physicians  who 
believed  in  the  spontaneity  of  disease,  and  he  wished 
to  wage  a  war  of  extermination  against  all  injurious 
organisms.  As  early  as  1850  Davaine  and  Rayer  had 
shown  that  a  rod-like  micro-organism  was  always  pres- 
ent in  the  blood  of  animals  dying  of  anthrax,  a  dis- 
ease which  was  destroying  the  flocks  and  herds  of 
France.  Dr.  Koch,  who  had  served  in  the  Franco- 
Prussian  War,  succeeded  in  1876  in  obtaining  pure 
cultures  of  this  bacillus  and  in  defining  its  relation 
to  the  disease.  Pasteur  took  up  the  study  of  anthrax 
in  1877,  verified  previous  discoveries,  and,  as  we  shall 
see,  sought  means  for  the  prevention  of  this  pest. 
He  discovered  (with  Joubert  and  Chamberland)  the 
bacillus  of  malignant  edema.  He  applied  the  prin- 
ciples of  bacteriology  to  the  treatment  of  puerperal 
fever,  which  in  1864  had  rendered  fatal  310  cases 
out  of  1350  confinements  in  the  Maternite  in  Paris. 
Here  he  had  to  fight  against  conservatism  in  the 


SCIENCE  AND  WAR  225 

medical  profession,  and  he  fought  strenuously,  one  of 
his  disciples  remarking  that  it  is  characteristic  of  lofty 
minds  to  put  passion  into  ideas.  Swine  plague,  which 
in  the  United  States  in  1879  destroyed  ove'jj  a  mil- 
lion hogs,  and  chicken  cholera,  also  engaged  his  at- 
tention. 

Cultures  of  chicken  cholera  virus  kept  for  some 
time  became  less  active.  A  hen  that  chanced  to  be 
inoculated  with  the  weakened  virus  developed  the 
disease,  but,  after  a  time,  recovered  (much  as  patiente 
after  the  old-time  smallpox  inoculations).  It  was  then 
inoculated  with  a  fresh  culture  supposed  sufficient 
to  cause  death.  It  again  recovered.  The  use  of  the 
weakened  inoculation  had  developed  its  resistance  to 
infection.  A  weakened  virus  recovered  its  strength 
when  passed  through  a  number  of  sparrows,  the  sec- 
ond being  inoculated  with  virus  from  the  first,  the 
third  from  the  second,  and  so  on  (this  species  being 
subject  to  the  disease).  Hens  that  had  not  had  chicken 
cholera  could  be  rendered  immune  by  a  series  of  at- 
tenuated inoculations  gradually  increasing  in  strength. 
In  the  case  of  anthrax  the  virus  could  be  weakened 
by  keeping  it  at  a  certain  temperature,  while  it  could 
be  strengthened  by  passage  through  a  succession  of 
guinea-pigs.  There  are  of  course  many  instances 
where  pathogenic  bacteria  lose  virulence  in  passing 
from  one  animal  to  another,  the  human  smallpox 
virus,  for  example,  producing  typical  cowpox  in  an 
inoculated  heifer.  These  facts  help  to  explain  why 
certain  infections  have  grown  less  virulent  in  the 
course  of  history,  and  why  infections  of  which  civil- 
ized man  has  become  tolerant  prove  fatal  when  im- 
parted to  the  primitive  peoples  of  Australia. 


226         THE  HISTORY  OF  SCIENCE 

Pasteur's  preventive  inoculation  for  anthrax  was 
tested  under  dramatic  circumstances  at  Melun  in 
June,  1881.  Sixty  sheep  and  a  number  of  cows  were 
subjected  to  experiment.  None  of  the  sheep  that  had 
been  given  the  preventive  treatment  died  from  the 
crucial  inoculation ;  while  all  those  succumbed  which 
had  not  received  previous  treatment.  The  test  for  the 
cows  was  likewise  successful.  Pasteur  thought  that 
in  places  where  sheep  dead  of  anthrax  had  been  buried, 
the  microbes  were  brought  to  the  surface  in  the  cast- 
ings of  earthworms.  Hence  he  issued  certain  direc- 
tions to  prevent  the  transmission  of  the  disease.  He 
also  aided  agriculture  by  discovering  a  vaccine  for 
swine  plague. 

When  Pasteur  at  the  age  of  fifteen  was  in  Paris, 
overcome  with  homesickness,  he  had  exclaimed,  "If 
I  could  only  get  a  whiff  of  the  old  tannery  yard, 
I  feel  I  should  be  cured."  Certainly  every  time  he 
came  in  contact  with  the  industries  —  silk,  wine,  beer, 
wool  —  his  scientific  insight,  Anta3us-like,  seemed  to 
revive.  All  his  life  he  had  preached  the  doctrine  of 
interchange  of  service  between  theory  and  practice, 
science  and  the  occupations.  What  he  did  is  more 
eloquent  than  words.  His  theory  of  molecular  dis- 
symmetry, that  the  atoms  in  a  molecule  may  be  ar- 
ranged in  left-hand  and  right-hand  spirals  or  other 
tridimensional  figures  corresponding  to  asymmetrical 
crystals,  touches  the  abstruse  question  of  the  consti- 
tution of  matter.  His  preventive  treatment  breathes 
new  life  into  the  old  dictum  similia  similibus  cu- 
rantur.  The  view  he  adopted  of  the  gradual  trans- 
formation of  species  offers  a  new  interpretation  of  the 
speculations  of  philosophy  in  reference  to  being  and 


SCIENCE  AND  WAR  227 

becoming  and  the  relation  of  the  real  to  the  concrete. 
Yet  Pasteur  felt  he  could  learn  much  of  value  from 
the  simplest  shepherd  or  vine-dresser. 

Pie  was  complete  in  the  simplicity  of  his  affec- 
tions, in  his  compassion  for  all  suffering,  in  the 
warmth  of  his  religious  faith,  and  in  his  devotion  to 
his  country.  He  thought  France  was  to  regain  her 
place  in  the  world's  esteem  through  scientific  prog- 
ress. He  was  therefore  especially  gratified  in  Au- 
gust, 1881,  at  the  thunders  of  applause  which 
greeted  his  appearance  at  the  International  Medical 
Congress  in  London.  There  he  was  introduced  to 
the  Prince  of  Wales  (fondateur  de  V Entente  Cor- 
diale),  "  to  whom  I  bowed,  saying  that  I  was 
happy  to  salute  a  friend  of  France." 

Pasteur's  investigation  of  rabies  began  in  this 
same  year.  Difficulty  was  found  in  isolating  the 
microbe  of  the  rabic  virus,  but  an  inoculation  from 
the  medulla  oblongata  of  a  mad  dog  injected  into 
one  of  the  brain  membranes  (dura  mater)  of  an- 
other dog  invariably  brought  on  the  symptoms  of 
rabies.  To  obtain  attenuation  of  the  virus  it  was 
sufficient  to  dry  the  medulla  taken  from  an  infected 
rabbit.  The  weakened  virus  increased  in  strength 
when  cultivated  in  a  series  of  rabbits.  Pasteur  ob- 
tained in  inoculations  of  graded  virulence,  which 
could  be  administered  hypodermically,  a  means  of 
prophylaxis  after  bites.  He  conjectured  that  in  vac- 
cinal  immunity  the  virus  is  accompanied  by  a  sub- 
stance which  makes  the  nervous  tissue  unfavorable 
for  the  development  of  the  microbe. 

It  was  not  till  1885  that  he  ventured  to  use  his 
discovery  to  prevent  hydrophobia.  On  July  6  a  little 


228         THE  HISTORY  OF  SCIENCE 

boy,  Joseph  Meister,  from  a  small  place  in  Alsace 
was  brought  by  his  mother  to  Paris  for  treatment. 
He  had  been  severely  bitten  by  a  mad  dog.  Pasteur, 
with  great  trepidation,  but  moved  by  his  usual  com- 
passion, undertook  the  case.  The  inoculations  of 
the  attenuated  virus  began  at  once.  The  boy  suf- 
fered little  inconvenience,  playing  about  the  labo- 
ratory during  the  ten  days  the  treatment  lasted. 
Pasteur  was  racked  with  fears  alternating  with 
hopes,  his  anxiety  growing  more  intense  as  the  viru- 
lence of  the  inoculations  increased.  On  August  20, 
however,  even  he  was  convinced  that  the  treatment 
was  a  complete  success.  In  October  a  shepherd  lad, 
who,  though  badly  bitten  himself,  had  saved  some 
other  children  from  the  attack  of  a  rabid  dog,  was 
the  second  one  to  benefit  by  the  great  discovery. 
Pasteur's  exchange  of  letters  with  these  boys  after 
they  had  returned  to  their  homes  reveals  the  kindli- 
ness of  his  disposition.  His  sentiment  toward  chil- 
dren had  regard  both  to  what  they  were  and  to  what 
they  might  become.  One  patient,  brought  to  him 
thirty-seven  days  after  being  bitten,  he  failed  to 
save.  By  March  1  Pasteur  reported  that  three  hun- 
dred and  fifty  cases  had  been  treated  with  only  one 
death. 

When  subscriptions  were  opened  for  the  erection 
and  endowment  of  the  Pasteur  Institute,  a  sum  of 
2,586,680  francs  was  received  in  contributions  from 
many  different  parts  of  the  world.  Noteworthy 
among  the  contributors  were  the  Emperor  of  Brazil, 
the  Czar  of  Eussia,  the  Sultan  of  Turkey,  and  the 
peasants  of  Alsace.  On  November  14,  1888,  Presi- 
dent Carnot  opened  the  institution,  which  was  soon 


SCIENCE  AND  WAR  229 

to  witness  the  triumphs  of  Roux,  Yersin,  Metchni- 
koff,  and  other  disciples  of  Pasteur.  In  the  address 
prepared  for  this  occasion  the  veteran  scientist 
wrote :  — 

"  If  I  might  be  allowed,  M.  le  President,  to  con- 
clude by  a  philosophical  remark,  inspired  by  your 
presence  in  this  home  of  work,  I  should  say  that 
two  contrary  laws  seem  to  be  wrestling  with  each 
other  at  the  present  time;  the  one  a  law  of  blood 
and  death,  ever  devising  new  means  of  destruc- 
tion and  forcing  nations  to  be  constantly  ready  for 
the  battlefield  —  the  other,  a  law  of  peace,  work, 
and  health,  ever  developing  new  means  of  delivering 
man  from  the  scourges  which  beset  him. 

"  The  one  seeks  violent  conquests,  the  other  the 
relief  of  humanity.  The  latter  places  one  human  life 
above  any  victory ;  while  the  former  would  sacrifice 
hundreds  and  thousands  of  lives  to  the  ambition  of 
one.  The  law  of  which  we  are  the  instruments 
seeks,  even  in  the  midst  of  carnage,  to  cure  the  san- 
guinary ills  of  the  law  of  war;  the  treatment  in- 
spired by  our  antiseptic  methods  may  preserve  thou- 
sands of  soldiers.  Which  of  these  two  laws  will 
ultimately  prevail  God  alone  knows.  But  we  may 
assert  that  French  science  will  have  tried,  by  obey- 
ing the  law  of  humanity,  to  extend  the  frontiers  of 
life." 


230         THE  HISTORY  OF  SCIENCE 


REFERENCES 

W.  W.  Ford,  The  Life  and  Work  of  Robert  Koch,  Bulletin  of  the 
Johns  Hopkins  Hospital,  Dec.  1911,  vol.  22. 

C.  A.  Herter,  The  Influence  of  Pasteur  on  Medical  Science,  Bul- 
letin of  the  Johns  Hopkins  Hospital,  Dec.  1903,  vol.  14. 

E.  O.  Jordan,  General  Bacteriology  (fourth  edition,  1915). 

Charles  C.  W.  Judd,  The  Life  and  Work  of  Lister,  Bulletin  of 
the  Johns  Hopkins  Hospital,  Oct.  1910,  vol.  21. 

Stephen  Paget,  Pasteur  and  After  Pasteur. 

W.  T.  Sedgwick,  Principles  of  Sanitary  Science. 

Rene  Vallery-Radot,  Life  of  Pasteur. 


CHAPTER  XVII 

SCIENCE    AND    INVENTION  -  —  LANGLEY's 
AEROPLANE 

IN  his  laudation  of  the  nineteenth  century  Alfred 
Russel  Wallace  ventured  to  enumerate  the  chief  in- 
ventions of  that  period:  (1)  Railways;  (2)  steam 
navigation;  (3)  electric  telegraphs;  (4)  the  tele- 
phone; (5)  friction  matches;  (6)  gas-lighting; 
(7)  electric-lighting;  (8)  photography;  (9)  the 
phonograph;  (10)  electric  transmission  of  power; 
(11)  Rontgen  rays;  (12)  spectrum  analysis;  (13) 
anaesthetics;  (14)  antiseptic  surgery.  All  preced- 
ing centuries  —  less  glorious  than  the  nineteenth  — 
can  claim  but  seven  or  eight  capital  inventions : 
(1)  Alphabetic  writing;  (2)  Arabic  numerals;  (3) 
the  mariner's  compass;  (4)  printing;  (5)  the  tele- 
scope; (6)  the  barometer  and  thermometer;  (7)  the 
steam  engine.  Similarly,  to  the  nineteenth  century 
thirteen  important  theoretical  discoveries  are  as- 
cribed, to  the  eighteenth  only  two,  and  to  the 
seventeenth  five. 

Of  course  the  very  purpose  of  these  lists — namely, 
to  compare  the  achievements  of  one  century  with 
those  of  other  centuries  —  inclines  us  to  view  each 
invention  as  an  isolated  phenomenon,  disregard- 
ing its  antecedents  and  its  relation  to  contempo- 
rary inventions.  Studied  in  its  development,  steam 
navigation  is  but  an  application  of  one  kind  of 
steam  engine,  and,  moreover,  must  be  viewed  as  a 


232         THE  HISTORY  OF  SCIENCE 

phase  in  the  evolution  of  navigation  since  the  earli- 
est times.  Like  considerations  would  apply  to  rail- 
ways, antiseptic  surgery,  or  friction  matches.  The 
nineteenth-century  inventor  of  the  friction  match 
was  certainly  no  more  ingenious  (considering  the 
means  that  chemistry  had  put  at  his  disposal) 
than  many  of  the  savages  who  contributed  by  their 
intelligence  to  methods  of  producing,  maintaining, 
and  using  fire.  In  fact,  as  we  approach  the  consid- 
eration of  prehistoric  times  it  becomes  difficult  to 
distinguish  inventions  from  the  slow  results  of  de- 
velopment —  in  metallurgy,  tool-making,  building, 
pottery,  war-gear,  weaving,  cooking,  the  domestica- 
tion of  animals,  the  selection  and  cultivation  of 
plants.  Moreover,  it  is  scarcely  in  the  category  of 
invention  that  the  acquisition  of  alphabetic  writing 
or  the  use  of  Arabic  numerals  properly  belongs. 

These  and  other  objections,  such  as  the  omission 
of  explosives,  firearms,  paper,  will  readily  occur  to 
the  reader.  Nevertheless,  these  lists,  placed  side  by 
side  with  the  record  of  theoretic  discoveries,  en- 
courage the  belief  that,  more  and  more,  sound  theory 
is  productive  of  useful  inventions,  and  that  hence- 
forth it  must  fall  to  scientific  endeavor  rather  than 
to  lucky  accident  to  strengthen  man's  control  over 
Nature.  Even  as  late  as  the  middle  of  the  nineteenth 
century  accident  and  not  science  was  regarded  as 
the  fountain-head  of  invention,  and  the  view  that  a 
knowledge  of  the  causes  and  secret  motions  of  things 
would  lead  to  "  the  enlarging  of  the  bounds  of  hu- 
man empire  to  the  effecting  of  all  things  possible  " 
was  scouted  as  the  idle  dream  of  a  doctrinaire. 

In  the  year  1896  three  important  advances  were 


SCIENCE  AND  INVENTION          233 

made  in  man's  mastery  of  his  environment.  These 
are  associated  with  the  names  of  Marconi,  Becquerel, 
and  Langley.  It  was  in  this  year  that  the  last-named, 
long  known  to  the  scientific  world  for  his  discoveries 
in  solar  physics,  demonstrated  in  the  judgment  of 
competent  witnesses  the  practicability  of  mechanical 
flight.  This  was  the  result  of  nine  years1  experimen- 
tation. It  was  followed  by  several  more  years  of 
fruitful  investigation,  leading  to  that  ultimate  tri- 
umph which  it  was  given  to  Samuel  Pierpont  Lang- 
ley  to  see  only  with  the  eye  of  faith. 

The  English  language  has  need  of  a  new  word 
("  plane")  to  signify  the  floating  of  a  bird  upon  the 
wing  with  slight,  or  no,  apparent  motion  of  the 
wings  (planer,  schweberi).  To  hover  has  other  con- 
notations, while  to  soar  is  properly  to  fly  upward, 
and  not  to  hang  poised  upon  the  air.  The  miracle  of 
a  bird's  flight,  that  steady  and  almost  effortless  mo- 
tion, had  interested  Langley  intensely  —  as  had  also 
the  sun's  radiation  —  from  the  years  of  his  childhood. 
The  phenomenon  (the  way  of  an  eagle  in  the  air) 
has  always,  indeed,  fascinated  the  human  imagina- 
tion and  at  the  same  time  baffled  the  comprehension. 
The  skater  on  smooth  ice,  the  ship  riding  at  sea, 
or  even  the  fish  floating  in  water,  offers  only  an 
incomplete  analogy ;  for  the  fish  has  approximately 
the  same  weight  as  the  water  it  displaces,  while  a 
turkey  buzzard  of  two  or  three  pounds'  weight  will 
circle  by  the  half-hour  on  motionless  wing  upheld 
only  by  the  thin  medium  of  the  air. 

In  1887,  prior  to  his  removal  to  Washington  as 
Secretary  of  the  Smithsonian  Institution,  Langley 
began  his  experiments  in  aerodynamics  at  the  old 


234         THE  HISTORY  OF  SCIENCE 

observatory  in  Allegheny — now  a  part  of  the  city 
of  Pittsburgh.  His  chief  apparatus  was  a  whirling 
table,  sixty  feet  in  diameter,  and  with  an  outside 
speed  of  seventy  miles  an  hour.  This  was  at  first 
driven  by  a  gas  engine,  —  ironically  named  "  Auto- 
matic,"—  for  which  a  steam  engine  was  substituted 
in  the  following  year.  By  means  of  the  whirling 
table  and  a  resistance-gauge  (dynamometer  chrono- 
graph) Langley  studied  the  effect  of  the  air  on 
planes  of  varying  lengths  and  breadths,  set  at  vary- 
ing angles,  and  borne  horizontally  at  different  veloc- 
ities. At  times  he  substituted  stuffed  birds  for  the 
metal  planes,  on  the  action  of  which  under  air  pres- 
sure his  scientific  deductions  were  based.  In  1891  he 
published  the  results  of  his  experiments.  These  proved 
— in  opposition  to  the  teaching  of  some  very  distin- 
guished scientists  —  that  the  force  required  to  sustain 
inclined  planes  in  horizontal  locomotion  through  the 
air  diminishes  with  increased  velocity  (at  least  within 
the  limits  of  the  experiment).  Here  a  marked  con- 
trast is  shown  between  aerial  locomotion  on  the  one 
hand,  and  land  and  water  locomotion  on  the  other ; 
"  whereas  in  land  or  marine  transport  increased  speed 
is  maintained  only  by  a  disproportionate  expenditure 
of  power,  within  the  limits  of  experiment  in  such 
aerial  horizontal  transport,  the  higher  speeds  are 
more  economical  of  power  than  the  lower  ones.19 
Again,  the  experiments  demonstrated  that  the  force 
necessary  to  maintain  at  high  velocity  an  apparatus 
consisting  of  planes  and  motors  could  be  produced 
by  means  already  available.  It  was  found,  for  ex- 
ample, that  one  horse-power  rightly  applied  is  suffi- 
cient to  maintain  a  plane  of  two  hundred  pounds  in 


SCIENCE  AND  INVENTION          235 

horizontal  flight  at  a  rate  of  about  forty-five  miles  an 
hour.  Langley  had  in  fact  furnished  experimental 
proof  that  the  aerial  locomotion  of  bodies  many  times 
heavier  than  air  was  possible.  He  reserved  for  fur- 
ther experimentation  the  question  of  aerodromics,  the 
form,  ascent,  maintenance  in  horizontal  position,  and 
descent  of  an  aerodrome  (aepoS/ooTio?,  traversing  the 
air),  as  he  called  the  prospective  flying  machine.  He 
believed,  however,  that  the  time  had  come  for  seriously 
considering  these  things,  and  intelligent  physicists, 
who  before  the  publication  of  Langley's  experiments 
had  regarded  all  plans  of  aerial  navigation  as  uto- 
pian,  soon  came  to  share  his  belief.  According  to  Oc- 
tave Chanute  there  was  in  Europe  in  1889  utter 
disagreement  and  confusion  in  reference  to  fun- 
damental questions  of  aerodynamics.  He  thought 
Langley  had  given  firm  ground  to  stand  upon  con- 
cerning air  resistances  and  reactions,  and  that  the 
beginning  of  the  solution  of  the  problem  of  aerial 
navigation  would  date  from  the  American  scientist's 
experiments  in  aerodynamics. 

Very  early  in  his  investigations  Langley  thought 
he  received  through  watching  the  anemometer  a  clue 
to  the  mystery  of  flight.  Observations,  begun  at  Pitts- 
burgh in  1887  and  continued  at  Washington  in  1893, 
convinced  him  that  the  course  of  the  wind  is  "  a  se- 
ries of  complex  and  little-known  phenomena,"  and 
that  a  wind  to  which  we  may  assign  a  mean  velocity 
of  twenty  or  thirty  miles  an  hour,  even  disregarding 
the  question  of  strata  and  currents,  is  far  from  being 
a  mere  mass  movement,  and  consists  of  pulsations 
varying  both  in  rate  and  direction  from  second  to  sec- 
ond. If  this  complexity  is  revealed  by  the  stationary 


236         THE  HISTORY  OF  SCIENCE 

anemometer — which  may  register  a  momentary  calm 
in  the  midst  of  a  gale  —  how  great  a  diversity  of 
pressure  must  exist  in  a  large  extent  of  atmosphere. 
This  internal  work  of  the  wind  will  lift  the  soaring 
bird  at  times  to  higher  levels,  from  which  without 
special  movement  of  the  wings  it  may  descend  in 
the  very  face  of  the  wind's  general  course. 

From  the  beginning,  however,  of  his  experiments 
Langley  had  sought  to  devise  a  successful  flying 
machine.  In  1887  and  the  following  years  he  con- 
structed about  forty  rubber-driven  models,  all  of 
which  were  submitted  to  trial  and  modification. 
From  these  tests  he  felt  that  he  learned  much  about 
the  conditions  of  flight  in  free  air  which  could  not 
be  learned  from  the  more  definitely  controlled  tests 
with  simple  planes  on  the  whirling  table.  His  essen- 
tial object  was,  of  course,  to  reduce  the  principles  of 
equilibrium  to  practice.  Besides  different  forms  and 
sizes  he  tried  various  materials  of  construction,  and 
ultimately  various  means  of  propulsion.  Before  he 
could  test  his  larger  steam-driven  models,  made  for 
the  most  part  of  steel  and  weighing  about  one  thou- 
sand times  as  much  as  the  air  displaced,  Langley 
spent  many  months  contriving  and  constructing 
suitable  launching  apparatus.  The  solution  of  the 
problem  of  safe  descent  after  flight  he  in  a  sense 
postponed,  conducting  his  experiments  from  a  house- 
boat on  the  Potomac,  where  the  model  might  come 
down  without  serious  damage. 

It  was  on  May  6,  1896  (the  anniversary  of  which 
date  is  now  celebrated  as  Langley  Day),  that  the 
success  was  achieved  which  all  who  witnessed  it  con- 
sidered decisive  of  the  future  of  mechanical  flight. 


THE  FIRST  SUCCESSFUL  HEAVIER-THAX-AIR  FLYIM!    MACHINE 

A  photograph  taken  at  the  moment  of  launching  Langley's  aerodrome 

May  6,  1896 


SCIENCE  AND  INVENTION          237 

The  whole  apparatus  —  steel  frame,  miniature  steam 
engine,  smoke  stack,  condensed-air  chamber,  gaso- 
line tank,  wooden  propellers,  wings  —  weighed  about 
twenty-four  pounds.  There  was  developed  a  steam 
pressure  of  about  115  pounds,  and  the  actual  power 
was  nearly  one  horse-power.  At  a  given  signal  the 
aeroplane  was  released  from  the  overhead  launching 
apparatus  on  the  upper  deck  of  the  house-boat.  It 
rose  steadily  to  an  ultimate  height  of  from  seventy 
to  a  hundred  feet.  It  circled  (owing  to  the  guys  of 
one  wing  being  loose)  to  the  right,  completing  two 
circles  and  beginning  a  third  as  it  advanced ;  so  that 
the  whole  course  had  the  form  of  a  spiral.  At  the 
end  of  one  minute  and  twenty  seconds  the  propellers 
began  to  slow  down  owing  to  the  exhaustion  of  fuel. 
The  aeroplane  descended  slowly  and  gracefully,  ap- 
pearing to  settle  on  the  water.  It  seemed  to  Alex- 
ander Graham  Bell  that  no  one  could  witness  this 
interesting  spectacle,  of  a  flying  machine  in  perfect 
equilibrium,  without  being  convinced  that  the  possi- 
bility of  aerial  flight  by  mechanical  means  had  been 
demonstrated.  On  the  very  day  of  the  test  he  wrote 
to  the  Academic  des  Sciences  that  there  had  never 
before  been  constructed,  so  far  as  he  knew,  a  heavier- 
than-air  flying  machine,  or  aerodrome,  which  could 
by  its  own  power  maintain  itself  in  the  air  for  more 
than  a  few  seconds. 

Langley  felt  that  he  had  now  completed  the  work 
in  this  field  which  properly  belonged  to  him  as  a 
scientist  —  "  the  demonstration  of  the  practicability 
of  mechanical  flight "  —  and  that  the  public  might 
look  to  others  for  its  development  and  commercial 
exploitation.  Like  Franklin  and  Davy  he  declined 


238         THE  HISTORY  OF  SCIENCE 

to  take  out  patents,  or  in  any  way  to  make  money 
from  scientific  discovery ;  and  like  Henry,  the  first 
Secretary  of  the  Smithsonian  Institution  (to  whom 
the  early  development  of  electro-magnetic  machines 
was  due),  he  preferred  to  be  known  as  a  scientist 
rather  than  as  an  inventor. 

Nevertheless,  Langley's  desire  to  construct  a  large, 
man-carrying  aeroplane  ultimately  became  irresist- 
ible. Just  before  the  outbreak  of  the  Spanish  War 
in  1898  he  felt  that  such  a  machine  might  be  of 
service  to  his  country  in  the  event  of  hostilities  that 
seemed  to  him  imminent.  The  attention  of  President 
McKinley  was  called  to  the  matter,  and  a  joint  com- 
mission of  Army  and  Navy  officers  was  appointed  to 
make  investigation  of  the  results  of  Professor  Lang- 
ley's  experiments  in.  aerial  navigation.  A  favorable 
report  having  been  made  by  that  body,  the  Board  of 
Ordnance  and  Fortification  recommended  a  grant  of 
fifty  thousand  dollars  to  defray  the  expenses  of  fur- 
ther research.  Langley  was  requested  to  undertake 
the  construction  of  a  machine  which  might  lead  to 
the  development  of  an  engine  of  war,  and  in  Decem- 
ber, 1898,  he  formally  agreed  to  go  on  with  the  work. 

He  hoped  at  first  to  obtain  from  manufacturers 
a  gasoline  engine  sufficiently  light  and  sufficiently 
powerful  for  a  man-carrying  machine.  After  several 
disappointments,  the  automobile  industry  being  then 
in  its  infancy,  he  succeeded  in  constructing  a  five- 
cylinder  gasoline  motor  of  fifty-two  horse-power  and 
weighing  only  about  a  hundred  and  twenty  pounds. 
He  also  constructed  new  launching  apparatus.  After 
tests  with  superposed  sustaining  surfaces,  he  adhered 
to  the  "single-tier  plan."  There  is  interesting  evi- 


SCIENCE  AND  INVENTION         239 

clence  that  in  1900  Langley  renewed  his  study  of  the 
flight  of  soaring  birds,  the  area  of  their  extended 
wing  surface  in  relation  to  weight,  and  the  vertical 
distance  between  the  center  of  pressure  and  the  cen- 
ter of  gravity  in  gulls  and  different  species  of  buz- 
zards. He  noted  among  other  things  that  the  tilting 
of  a  wing  was  sufficient  to  bring  about  a  complete 
change  of  direction. 

By  the  summer  of  1903  two  new  machines  were 
ready  for  field  trials,  which  were  undertaken  from  a 
large  house-boat,  especially  constructed  for  the  pur- 
pose and  then  moored  in  the  mid-stream  of  the 
Potomac  about  forty  miles  below  Washington.  The 
larger  of  these  two  machines  weighed  seven  hundred 
and  five  pounds  and  was  designed  to  carry  an  en- 
gineer to  control  the  motor  and  direct  the  flight. 
The  motive  power  was  supplied  by  the  light  and 
powerful  gasoline  engine  already  referred  to.  The 
smaller  aeroplane  was  a  quarter-size  model  of  the 
larger  one.  It  weighed  fifty-eight  pounds,  had  an  en- 
gine of  between  two  and  a  half  and  three  horse-power, 
and  a  sustaining  surface  of  sixty-six  square  feet. 

This  smaller  machine  was  tested  August  8,  1903, 
the  same  launching  apparatus  being  employed  as 
with  the  steam-driven  models  of  1896.  In  spite  of 
the  fact  that  one  of  the  mechanics  failed  to  withdraw 
a  certain  pin  at  the  moment  of  launching,  and  that 
some  breakage  of  the  apparatus  consequently  oc- 
curred, the  aeroplane  made  a  good  start,  and  fulfilled 
the  main  purpose  of  the  test  by  maintaining  a  per- 
fect equilibrium.  After  moving  about  three  hundred 
and  fifty  feet  in  a  straight  course  it  wheeled  a  quar- 
ter-circle to  the  right,  at  the  same  time  descending 


240         THE  HISTORY  OF  SCIENCE 

slightly,  the  engine  slowing  down.  Then  it  began  to 
rise,  moving  straight  ahead  again  for  three  or  four 
hundred  feet,  the  propellers  picking  up  their  former 
rate.  Once  more  the  engine  slackened,  but,  before 
the  aeroplane  reached  the  water,  seemed  to  regain 
its  normal  speed.  For  a  third  time  the  engine  slowed 
down,  and,  before  it  recovered,  the  aeroplane  had 
touched  the  water.  It  had  traversed  a  distance  of 
one  thousand  feet  in  twenty-seven  seconds.  One  of 
the  workmen  confessed  that  he  had  poured  into  the 
tank  too  much  gasoline.  This  had  caused  an  overflow 
into  the  intake  pipe,  which  in  turn  interfered  with 
the  action  of  a  valve. 

The  larger  aeroplane  with  the  engineer  Manly  on 
board  was  first  tested  on  October  7  of  the  same  year, 
but  the  front  guy  post  caught  in  the  launching  car 
and  the  machine  plunged  into  the  water  a  few  feet 
from  the  house-boat.  In  spite  of  this  discouraging 
mishap  the  engineers  and  others  present  felt  confi- 
dence in  the  aeroplane's  power  to  fly.  What  would 
to-day  be  regarded  by  an  aeronaut  as  a  slight  set- 
back seemed  at  that  moment  like  a  tragic  failure. 
The  fifty  thousand  dollars  had  been  exhausted  nearly 
two  years  previously ;  Professor  Langley  had  made 
as  full  use  as  seemed  to  him  advisable  of  the  resources 
put  at  his  disposal  by  the  Smithsonian  Institution ; 
the  young  men  of  the  press,  for  whom  the  supposed 
aberration  of  a  great  scientist  furnished  excellent 
copy,  were  virulent  in  their  criticisms.  Manly  made 
one  more  heroic  attempt  under  very  unfavorable  con- 
ditions at  the  close  of  a  winter's  day  (December  8, 
1903).  Again  difficulty  occurred  with  the  launching 
gear,  the  rear  wings  and  rudder  being  wrecked  be- 


SCIENCE  AND  INVENTION          241 

fore  the  aeroplane  was  clear  of  the  ways.  The  exper- 
iments were  now  definitely  abandoned,  and  the  in- 
ventor was  overwhelmed  by  the  sense  of  failure,  and 
still  more  by  the  skepticism  with  which  the  publio 
had  regarded  his  endeavors. 

In  1905  an  account  of  Langley's  aeroplane  ap- 
peared in  the  Bulletin  of  the  Italian  Aeronautical 
Society.  Two  years  later  this  same  publication  in 
an  article  on  a  new  Bldriot  aeroplane  said :  "  The 
Ble*riot  IV  in  the  form  of  a  bird  .  .  .  does  not  ap- 
pear to  give  good  results,  perhaps  on  account  of  the 
lack  of  stability,  and  Ble*riot,  instead  of  trying  some 
new  modification  which  might  remedy  such  a  grave 
fault,  laid  it  aside  and  at  once  began  the  construc- 
tion of  a  new  type,  No.  V,  adopting  purely  and  sim- 
ply the  arrangement  of  the  American,  Langley,  which 
offers  a  good  stability."  In  the  summer  of  1907 
Ble*riot  obtained  striking  results  with  this  machine, 
the  launching  problem  having  been  solved  in  the 
previous  year  —  the  year  of  Langley's  death  —  by 
the  use  of  wheels  which  permitted  the  aeroplane  to 
get  under  way  by  running  along  the  ground  under 
its  own  driving  power.  The  early  flights  with  No.  V 
were  made  at  a  few  feet  from  the  ground,  and  the 
clever  French  aviator  could  affect  the  direction  of 
the  machine  by  slightly  shifting  his  position,  and 
even  had  skill  to  bring  it  down  by  simply  leaning 
forward.  By  the  use  of  the  steering  apparatus  he 
circled  to  the  right  or  to  the  left  with  the  grace  of 
a  bird  on  the  wing.  When,  on  July  25, 1909,  Bldriot 
crossed  the  English  Channel  in  his  monoplane,  all 
the  world  knew  that  man's  conquest  of  the  air  was  a 
fait  accompli. 


THE  HISTORY  OF  SCIENCE 

About  three  years  after  Langley 's  death  the  Board  of 
Regents  of  the  Smithsonian  Institution  established  the 
Langley  Medal  for  investigations  in  aerodromics  in  its 
application  to  aviation.  The  first  award  went  (1909) 
to  Wilbur  and  Orville  Wright,  the  second  (1913) 
to  Mr.  Glenn  H.  Curtiss  and  M.  Gustave  Eiffel.  On 
the  occasion  of  the  presentation  of  the  medals  of  the 
second  award  —  May  6,  1913  —  the  Langley  Me- 
morial Tablet,  erected  in  the  main  vestibule  of  the 
Smithsonian  building,  was  unveiled  by  the  scientist's 
old  friend,  Dr.  John  A.  Brashear.  In  the  words  of 
the  present  Secretary  of  the  Institution,  the  tablet 
represents  Mr.  Langley  seated  on  a  terrace  where 
he  has  a  clear  view  of  the  heavens,  and,  in  a  medita- 
tive mood,  is  observing  the  flight  of  birds,  while  in 
his  mind  he  sees  his  aerodrome  soaring  above  them. 

The  lettering  of  the  tablet  is  as  follows :  — 

SAMUEL  PIERPONT  LANGLEY 
1834-1906 

SECRETARY   OF  THE   SMITHSONIAN   INSTITUTION 
1887-1906 


DISCOVERED  THE  RELATIONS  OF  SPEED 

AND   ANGLE    OF   INCLINATION   TO   THE 

LIFTING    POWER    OF    SURFACES   WHEN 

MOVING   IN   AIR 


"I  have  brought  to  a  close  the  portion  of  the 
work  which  seemed  to  be  especially  mine,  the 
demonstration  of  the  practicability  of  mechan- 
ical flight." 

"The  great  universal  highway  overhead  is  now 
soon  to  be  opened."  —  Langley,  1897. 


SCIENCE  AND  INVENTION          243 

A  still  more  fitting  tribute  to  the  memory  of  the 
great  inveiitor  came  two  years  later  from  a  success- 
ful aviator.  In  the  spring  of  1914  Mr.  Glenn  H. 
Curtiss  was  invited  to  send  apparatus  to  Washing- 
ton for  the  Langley  Day  Celebration.  He  expressed 
the  desire  to  put  the  Langley  aeroplane  itself  in  the 
air.  The  machine  was  taken  to  the  Curtiss  Aviation 
Field  at  Keuka  Lake,  New  York.  Langley's  method 
of  launching  had  been  proved  practical,  but  Curtiss 
finally  decided  to  start  from  the  water,  and  accord- 
ingly fitted  the  aeroplane  with  hydroaeroplane  floats. 
In  spite  of  the  great  increase  in  weight  involved  by 
this  addition,  the  Langley  aeroplane,  under  its  own 
power  plant,  skimmed  over  the  wavelets,  rose  from 
the  lake,  and  soared  gracefully  in  the  air,  maintain- 
ing its  equilibrium,  on  May  28,  1914,  over  eight 
years  after  the  death  of  its  designer.  When  furnished 
with  an  eighty  horse-power  motor,  more  suited  to  its 
increased  weight,  the  aerodrome  planed  easily  over  the 
water  in  more  prolonged  flight.  In  the  periodical 
publications  of  June,  1914,  may  be  read  the  eloquent 
announcement :  "  Langley's  Folly  Flies." 


244        THE  HISTORY  OF  SCIENCE 


REFERENCES 

Alexander  Graham  Bell,  Experiments  in  Mechanical  Flight, 
Nature,  May  28,  1896. 

Alexander  Graham  Bell,  The  Pioneer  Aerial  Flight,  Scientific 
American,  Supplement,  Feb.  26,  1910. 

S.  P.  Langley,  Experiments  in  Aerodynamics. 

S.  P.  Langley,  The  "  Flying  Machine,"  McClure's,  June,  1897 
(illustrated). 

Langley  Memoir  on  Mechanical  Flight,  Smithsonian  Contributions 
to  Knowledge,  vol.  27,  no.  3  (illustrated). 

Scientific  American,  Jan.  13,  1912,  A  Memorial  Honor  to  a 
Pioneer  Inventor. 

The  Smithsonian  Institution  1846-1896.  The  History  of  its  First 
Half-Century,  edited  by  G.  B.  Goode. 

A.  F.  Zahm,  The  First  Man-carrying  Aeroplane  capable  of  Sus- 
tained Free  Flight,  Annual  Report  of  the  Smithsonian  Insti- 
tution, 1914  (illustrated). 


CHAPTER  XVIII 

SCIENTIFIC    HYPOTHESIS RADIOACTIVE 

SUBSTANCES 

THE  untrained  mind,  reliant  on  so-called  facts  and 
distrustful  of  mere  theory,  inclines  to  think  of  truth 
as  fixed  rather  than  progressive,  static  rather  than 
dynamic.  It  longs  for  certainty  and  repose,  and  has 
little  patience  for  any  authority  that  does  not  claim 
absolute  infallibility .-[  Many  a  man  of  the  world  is 
bewildered  to  find  Newton's  disciples  building  upon 
or  refuting  the  teachings  of  the  master,  or  to  learn 
that  Darwin's  doctrine  is  itself  subject  to  the  univer- 
sal law  of  change  and  development.  Though  in  ethics 
and  religion  the  older  order  changes  yielding  place  to 
new,  and  the  dispensation  of  an  eye  for  an  eye  and 
a  tooth  for  a  tooth  finds  its  fulfilment  and  culmina- 
tion in  a  dispensation  of  forbearance  and  non-resist- 
ance of  evil,  still  many  look  upon  the  overthrow  of 
any  scientific  theory  not  as  a  sign  of  vitality  and  ad- 
vance, but  as  a  symptom  of  the  early  dissolution  or 
at  least  of  the  bankruptcy  of  science.  It  is  not  sur- 
prising, therefore,  that  the  public  regard  the  scientific 
hypothesis  with  a  kind  of  contempt ;  for  a  hypothesis 
(i>7ro^ecrt9,  foundation,  supposition)  is  necessarily 
ephemeral.  When  disproved,  it  is  shown  to  have  been 
a  false  supposition;  when  proved,  it  is  no  longer 
hypothetic. 

Yet  a  page  from  the  history  of  science  should  in- 
dicate that  hypotheses  play  a  role  in  experimental 


246         THE  HISTORY  OF  SCIENCE 

science  and  lead  to  results  that  no  devotee  of  facts 
and  scorner  of  mere  theory  can  well  ignore. 

In  1895  Sir  William  Ramsay,  who  in  the  previous 
year  had  discovered  an  inert  gas,  argon,  in  the  at- 
mosphere, identified  a  second  inert  gas  (obtained 
from  minerals  containing  uranium  and  thorium)  as 
helium  (rJXto?,  sun),  an  element  previously  revealed 
by  spectrum  analysis  as  a  constituent  of  the  sun.  In 
the  same  year  Rontgen,  while  experimenting  with  the 
rays  that  stream  from  the  cathode  in  a  vacuum  tube, 
discovered  new  rays  (which  he  called  X-rays)  pos- 
sessed of  wonderful  photographic  power.  At  the  be- 
ginning of  1896  Henri  Becquerel,  experimenting  on 
the  supposition,  or  hypothesis,  that  the  emission  of 
rays  was  associated  with  phosphorescence,  tested  the 
photographic  effects  of  a  number  of  phosphorescent 
substances.  He  exposed,  among  other  compounds, 
crystals  of  the  double  sulphate  of  uranium  and  po- 
tassium to  sunlight  and  then  placed  upon  the  crystals 
a  photographic  plate  wrapped  in  two  thicknesses  of 
heavy  black  paper.  The  outline  of  the  phosphorescent 
substance  was  developed  on  the  plate.  An  image  of  a 
coin  was  obtained  by  placing  it  between  uranic  salts 
and  a  photographic  plate.  Two  or  three  days  after 
reporting  this  result  Becquerel  chanced  (the  sunlight 
at  the  time  seeming  to  him  too  intermittent  for  ex- 
perimentation) to  put  away  in  the  same  drawer,  and  in 
juxtaposition,  a  photographic  plate  and  these  phos- 
phorescent salts.  To  his  surprise  he  obtained  a  clear 
image  when  the  plate  was  developed.  He  now  assumed 
the  existence  of  invisible  rays  similar  to  X-rays. 
They  proved  capable  of  passing  through  sheets  of 
aluminum  and  of  copper,  and  of  discharging  electri- 


SCIENTIFIC  HYPOTHESIS  247 

fiecl  bodies.  Days  elapsed  without  any  apparent  dimi- 
nution of  the  radiation.  On  the  supposition  that  the 
rays  might  resemble  light  he  tried  to  refract,  reflect, 
and  polarize  them  ;  but  this  hypothesis  was  by  the  ex- 
periments of  Rutherford,  and  of  Becquerel  himself, 
ultimately  overthrown.  In  the  mean  time  the  French 
scientist  obtained  radiations  from  metallic  uranium 
and  from  uranous  salts.  These,  in  contrast  with 
the  uranic  salts,  are  non-phosphorescent.  Becquerel's 
original  hypothesis  was  thus  overthrown.  Radiation 
is  a  property  inherent  in  uranium  and  independent 
both  of  light  and  of  phosphorescence. 

On  April  13  and  April  23  (1898)  respectively 
Mine.  Sklodowska  Curie  and  G.  C.  Schmidt  pub- 
lished the  results  of  their  studies  of  the  radiations 
of  the  salts  of  thorium.  Each  of  these  studies  was 
based  on  the  work  of  Becquerel.  Mme.  Curie  ex- 
amined at  the  same  time  the  salts  of  uranium  and  a 
number  of  uranium  ores.  Among  the  latter  she 
made  use  of  the  composite  mineral  pitchblende  from 
the  mines  of  Joachimsthal  and  elsewhere,  and  found 
that  the  radiations  from  the  natural  ores  are  more 
active  than  those  from  pure  uranium.  This  discovery 
naturally  led  to  further  investigation,  on  the  assump- 
tion that  pitchblende  contains  more  than  one  radio- 
active substance.  Polonium,  named  by  Mme.  Curie 
in  honor  of  her  native  country,  was  the  third  radio- 
active element  to  be  discovered.  In  the  chemical 
analysis  of  pitchblende  made  by  Mme.  Curie  (as- 
sisted by  M.  Curie)  polonium  was  found  associated 
with  bismuth.  Radium,  also  discovered  in  this  anal- 
ysis of  1898,  was  associated  with  barium.  Mme. 
Curie  succeeded  in  obtaining  the  pure  chloride  of 


248         THE  HISTORY  OF  SCIENCE 

radium  and  in  determining  the  atomic  weight  of  the 
new  element.  There  is  (according  to  Soddy)  about 
one  part  of  radium  in  five  million  parts  of  the  best 
pitchblende,  but  the  new  element  is  about  one  mil- 
lion times  more  radioactive  than  uranium.  It  was 
calculated  by  M.  Curie  that  the  energy  of  one  gram 
of  radium  would  suffice  to  lift  a  weight  of  five  hun- 
dred tons  to  a  height  of  one  mile.  After  discussing 
the  bearing  of  the  discovery  of  radioactivity  on  the 
threatened  exhaustion  of  the  coal  supply  Soddy 
writes  enthusiastically :  "  But  the  recognition  of  the 
boundless  and  inexhaustible  energy  of  Nature  (and 
the  intellectual  gratification  it  affords)  brightens  the 
whole  outlook  of  the  twentieth  century."  The  ele- 
ment yields  spontaneously  radium  emanation  without 
any  apparent  diminution  of  its  own  mass.  In  1899 
Debierne  discovered,  also  in  the  highly  complex 
pitchblende,  actinium,  which  has  proved  considerably 
less  radioactive  than  radium.  During  these  investi- 
gations M.  and  Mme.  Curie,  M.  Becquerel,  and  those 
associated  with  them  were  influenced  by  the  hypoth- 
esis that  radioactivity  is  an  atomic  property  of  radio- 
active substances.  This  hypothesis  came  to  definite 
expression  in  1899  and  again  in  1902  through  Mme. 
Curie. 

In  the  latter  year  the  physicist  E.  Rutherford  and 
the  chemist  F.  Soddy,  while  investigating  the  radio- 
activity of  thorium  in  the  laboratories  of  McGill 
University,  Montreal,  were  forced  to  recognize  that 
thorium  continuously  gives  rise  to  new  kinds  of  ra- 
dioactive matter  differing  from  itself  in  chemical 
properties,  in  stability,  and  in  radiant  energy.  They 
concurred  in  the  view  held  by  all  the  most  prominent 


SCIENTIFIC  HYPOTHESIS  249 

workers  in  this  subject,  namely,  that  radioactivity  is 
an  atomic  phenomenon.  It  is  not  molecular  decompo- 
sition. They  declared  that  the  radioactive  substances 
must  be  undergoing  a  spontaneous  transformation. 
The  daring  nature  of  this  hypothesis  and  its  likeli- 
hood to  revolutionize  physical  science  is  brought  home 
to  one  by  recalling  that  three  decades  previously  an 
eminent  physicist  had  said  that  "though  in  the 
course  of  ages  catastrophes  have  occurred  and  may 
yet  occur  in  the  heavens,  though  ancient  systems 
may  be  dissolved  and  new  systems  evolved  out  of 
their  ruins,  the  molecules  [atoms]  out  of  which  these 
systems  are  built  —  the  foundation  stones  of  the 
material  universe  —  remain  unbroken  and  unworn." 
In  1903  Rutherford  and  Soddy  stated  definitely 
their  hypothesis,  generally  known  as  the  "  Transfor- 
mation Theory,"  that  the  atoms  of  radioactive  sub- 
stances suffer  spontaneous  disintegration,  a  process 
unaffected  by  great  changes  of  temperature  (or  by 
physical  or  chemical  changes  of  any  kind  at  the  dis- 
posal of  the  experimenter)  and  giving  rise  to  new 
radioactive  substances  differing  in  chemical  (and 
physical)  properties  from  the  parent  elements.  The 
radiations  consist  of  a  particles  (atoms  of  helium 
minus  two  negative  electrons),  (B  particles,  or  elec- 
trons (charges  of  negative  electricity),  and  7  rays,  of 
the  nature  of  Rontgen  rays  and  light  but  of  very  much 
shorter  wave  length  and  of  very  great  penetrating 
power.  It  is  by  the  energy  inherent  in  the  atom  of  the 
radioactive  substance  that  the  radiations  are  ejected, 
sometimes,  in  the  case  of  the  7  rays  with  velocity 
sufficient  to  penetrate  two  feet  of  lead.  It  is  through 
these  radiations  that  spontaneous  transformation 


250         THE  HISTORY  OF  SCIENCE 

takes  place.  After  ten  years  of  further  investigation 
Rutherford  stated  that  this  hypothesis  affords  a 
satisfactory  explanation  of  all  radioactive  phenom- 
ena, and  gives  unity  to  what  without  it  would  seem 
disconnected  facts.  Besides  accounting  for  old  ex- 
perimental results  it  suggests  new  lines  of  work 
and  even  enables  one  to  predict  the  outcome  of  fur- 
ther investigation.  It  does  not  really  contradict,  as 
some  thought  might  be  the  case,  the  principle  of  the 
conservation  of  energy.  The  atom,  to  be  sure,  can 
no  longer  be  considered  the  smallest  unit  of  matter, 
as  the  mass  of  a  /3  particle  is  approximately  one 
seventeen-hundredths  that  of  an  atom  of  hydrogen. 
Still  the  new  hypothesis  is  a  modification  and  not  a 
contradiction  of  the  atomic  theory. 

The  assumption  that  the  series  of  radioactive  sub- 
stances is  due,  not  to  such  molecular  changes  as  chem- 
istry had  made  familiar,  but  to  a  breakdown  of  the 
atom  seemed  to  Rutherford  in  1913  at  least  justified 
by  the  results  of  the  investigators  whose  procedure 
had  been  dictated  by  that  hypothesis.  He  set  forth 
in  tables  these  results  (since  somewhat  modified), 
indicating  after  the  name  of  each  radioactive  sub- 
stance the  nature  of  the  radiation  through  the  emis- 
sion of  which  the  element  is  transformed  into  the 
next-succeeding  member  of  its  series. 

List  of  Radioactive  Substances 

URANIUM  a  particles 

Uranium  X 
Uranium  Y 
IONIUM 


SCIENTIFIC  HYPOTHESIS  251 


RADIUM 

a  +  slow  ft 

Emanation 

a 

Radium  A 

a 

Radium  B 

ft+y 

Radium  C  j     * 
(.  C2 

a  +  ft  +  y 

RADIUM  D 
RADIO-LEAD 

|  slow  ft 

Radium  E 

ft  +  y 

Radium  F 

Polonium 

THORIUM 

a 

MESOTHORIUM  1 

no  rays 

Mesothorium  2 

ft+y 

RADIOTHORIUM 

a 

Thorium  X 

a  +  ft 

Emanation 

a 

Thorium  A 

a 

Thorium  B 

slow  ft 

{C1 
(_/g 

a 
a 

Thorium  D 

ft  +  y 

ACTINIUM 

no  rays 

Radio-actinium 

a  +  ft 

Actinium  X 

a 

Emanation 

a 

Actinium  A 

a 

Actinium  B 

slow  8 

Actinium  C 

a 

Actinium  D 

a  +  y 

252         THE  HISTORY  OF  SCIENCE 

Even  a  glance  at  this  long  list  of  new  elements 
reveals  certain  analogies  between  one  series  of  trans- 
formations and  another.  Each  series  contains  an  ema- 
nation, or  gas,  which  through  the  loss  of  a  particles 
is  transformed  into  the  next  following  member  of  the 
series.  Continuing  the  comparison  in  either  direction, 
up  or  down  the  lists,  one  could  readily  detect  other 
analogies. 

There  is  some  ground  for  thinking  that  lead  is  the 
end  product  of  the  Uranium  series.  To  reverse  the 
process  of  the  transformation  and  produce  radium  from 
the  base  metal  lead  would  be  an  achievement  greater 
than  the  vaunted  transmutations  of  the  alchemists. 
Although  that  seems  beyond  the  reach  of  possibility, 
the  idea  has  stirred  the  imagination  of  more  than  one 
scientist.  "The  philosopher's  stone,"  writes  Soddy, 
"  was  accredited  the  power  not  only  of  transmuting 
the  metals,  but  of  acting  as  the  elixir  of  life.  Now, 
whatever  the  origin  of  this  apparently  meaningless 
jumble  of  ideas  may  have  been,  it  is  really  a  perfect 
and  but  very  slightly  allegorical  expression  of  the 
actual  present  views  we  hold  to-day."  Again,  it  is 
conjectured  that  bismuth  is  the  end-product  of  the 
thorium  series.  The  presence  of  the  results  of  atomic 
disintegration  (like  lead  and  helium)  has  proved  of 
interest  to  geology  and  other  sciences  as  affording  a 
clue  to  the  age  of  the  rocks  in  which  they  are  found 
deposited. 

Before  Rutherford,  Mme.  Curie,  and  others  espe- 
cially interested  in  radioactive  substances,  assumed 
that  atoms  are  far  different  from  the  massy,  hard,  im- 
penetrable particles  that  Newton  took  for  granted, 
Sir  J.  J.  Thomson  and  his  school  were  studying  the 


SCIENTIFIC  HYPOTHESIS  253 

constitution  of  the  atom  from  another  standpoint  but 
with  somewhat  similar  results.  This  great  physicist 
had  proved  that  cathode  rays  are  composed  not  of 
negatively  charged  molecules,  as  had  been  supposed, 
but  of  much  smaller  particles  or  corpuscles.  Wherever, 
as  in  the  vacuum  tube,  these  electrons  appear,  the 
presence  of  positively  charged  particles  can  also  be 
demonstrated.  It  is  manifest  that  the  atom,  instead 
of  being  th3  ultimate  unit  of  matter,  is  a  system  of 
positively  and  negatively  chasged  particles.  Ruther- 
ford in  the  main  concurred  in  this  view,  though  dif- 
fering from  Sir  J.  J.  Thomson  as  to  the  arrangement 
of  corpuscles  within  the  atom.  Let  it  suffice  here  to 
state  that  Rutherford  assumes  that  the  greater  mass 
of  the  atom  consists  of  negatively  charged  particles 
rotating  about  a  positive  nucleus.  The  surrounding 
electrons  render  the  atom  electrically  neutral. 

This  corpuscular  theory  of  matter  may  throw  light 
on  the  laws  of  chemical  combination.  The  so-called 
chemical  affinity  between  two  atoms  of  such  and  such 
valencies,  which  Davy  and  others  since  his  time  had 
regarded  as  essentially  an  electrical  phenomenon, 
seems  now  to  admit  of  more  definite  interpretation. 
Each  atom  is  negatively  or  positively  charged  accord- 
ing to  the  addition  or  subtraction  of  electrons.  Chemi- 
cal composition  takes  place  between  atoms  the  charges 
of  which  are  of  opposite  sign,  and  valency  depends  on 
the  number  of  unit  charges  of  electricity.  Moreover, 
the  electrical  theory  of  matter  lends  support  to  the  hy- 
pothesis that  there  is  a  fundamental  unitary  element 
underlying  all  the  so-called  elements.  The  fact  that 
elements  fall  into  groups  and  that  their  chemical  prop- 
erties vary  with  their  atomic  weights  long  ago  sug- 


254         THE  HISTORY  OF  SCIENCE 

gested  this  assumption  of  a  primitive  matter,  protyl, 
from  which  all  other  substances  were  derived.  In  the 
light  of  the  corpuscular  theory  as  well  as  of  the  trans- 
formation theory  it  seems  possible  that  the  helium 
atom  and  the  negative  corpuscle  will  offer  a  clue  to 
the  genesis  of  the  elements. 

What  is  to  be  learned  from  this  rapid  sketch,  of 
the  discovery  of  the  radioactive  substances,  concern- 
ing the  nature  and  value  of  scientific  hypothesis? 
For  one  thing,  the  scientific  hypothesis  is  necessary 
to  the  experimenter.  The  mind  runs  ahead  of  and 
guides  the  experiment.  Again,  the  hypothesis  sug- 
gests new  lines  of  research,  enables  one  in  some  cases 
to  anticipate  the  outcome  of  experiment,  and  may  be 
abundantly  justified  by  results.  "It  is  safe  to  say," 
writes  Rutherford,  "  that  the  rapidity  of  growth  of 
accurate  knowledge  of  radioactive  phenomena  has 
been  largely  due  to  the  influence  of  the  disintegration 
theory."  The  valid  hypothesis  serves  to  explain  facts, 
leads  to  discovery,  and  does  not  conflict  with  known 
facts  or  with  verified  generalizations,  though,  as  we 
have  seen,  it  may  modify  other  hypo  theses  J*Those 
who  support  a  hypothesis  should  bring  it  to  the  test 
of  rigid  verification,  avoiding  skepticism,  shunning 
credulity.  lEven  a  false  assumption,  as  we  have  seen, 
may  prove  valuable  when  carefully  put  to  the  proof. 

The  layman's  distrust  of  the  unverified  hypothesis 
is  in  the  main  wholesome.  It  is  a  duty  not  to  believe 
it,  not  to  disbelieve  it,  but  to  weigh  judicially  the  evi- 
dence for  and  against.  The  fact  that  assumption  plays 
a  large  part  in  our  mental  attitude  toward  practical 
affairs  should  make  us  wary  of  contesting  the  legiti- 
macy of  scientific  hypotheses. 


SCIENTIFIC  HYPOTHESIS  255 

No  one  would  deny  the  right  of  forming  a  provi- 
sional assumption  to  the  intelligence  officer  interpret- 
ing a  cipher,  or  to  the  detective  unravelling  the  mys- 
tery of  a  crime.  The  first  assumes  that  the  message 
is  in  a  certain  language,  and,  perhaps,  that  each  sym- 
bol employed  is  the  equivalent  of  a  letter ,  his  assump- 
tion is  put  to  the  proof  of  getting  a  reasonable  and 
consistent  meaning  from  the  cipher.  The  detective 
assumes  a  motive  for  the  crime,  or  the  employment 
of  certain  means  of  escape ;  even  if  his  assumption 
does  not  clear  up  the  mystery,  it  may  have  value  as 
leading  to  a  new  and  more  adequate  assumption. 

Henri  Poincare  has  pointed  out  that  one  of  the 
most  dangerous  forms  of  hypothesis  is  the  uncon- 
scious hypothesis.  It  is  difficult  to  prove  or  disprove 
because  it  does  not  come  to  clear  statement.  The  al- 
leged devotee  of  facts  and  of  things  as  they  are,  in 
opposing  the  assumptions  of  an  up-to-date  science,  is 
often,  unknown  to  himself,  standing  on  a  platform 
of  outworn  theory,  or  of  mere  vulgar  assumption. 
For  example,  when  Napoleon  was  trying  to  destroy 
the  commercial  wealth  of  England  at  the  beginning 
of  the  nineteenth  century,  he  unconsciously  based  his 
procedure  on  an  antiquated  doctrine  of  political 
economy.  For  him  the  teachings  of  Adam  Smith  and 
Turgot  were  idle  sophistries.  "  I  seek,"  he  said  to 
his  Minister  of  Finance,  "the  good  that  is  prac- 
tical, not  the  ideal  best :  the  world  is  very  old ,  we 
must  profit  by  its  experience;  it  teaches  that  old 
practices  are  worth  more  than  new  theories :  you  are 
not  the  only  one  who  knows  trade  secrets."  We  are 
not  here  especially  concerned  with  the  question  of 
whether  Napoleon  was  or  was  not  pursuing  the  best 


256         THE  HISTORY  OF  SCIENCE 

means  of  breaking  down  English  credit.  He  did  try 
to  prevent  the  English  from  exchanging  exports  for 
European  gold,  while  permitting  imports  in  the  hope 
of  depleting  England  of  gold.  But  in  pursuing  this 
policy  he  thought  he  was  proceeding  on  the  ground 
of  immemorial  practice,  while  he  was  merely  pitting 
the  seventeenth-century  doctrine  of  Locke  against 
the  doctrine  of  Adam  Smith  which  had  superseded  it. 

According  to  one  scientific  hypothesis,  "Species 
originated  by  means  of  natural  selection,  or,  through 
the  preservation  of  favored  races  in  the  struggle  for 
life."  This  assumption  was  rightly  subjected  to  close 
scrutiny  in  1859  and  the  years  following.  The  ephem- 
eral nature  of  the  vast  majority  of  hypotheses  and 
the  danger  to  progress  of  accepting  an  unverified 
assumption  justify  the  demand  for  demonstrative 
evidence.  The  testimony  having  been  examined,  it 
is  our  privilege  to  state  and  to  support  the  opposing 
hypothesis.  It  was  thus  that  the  hypothesis  that  the 
planets  move  in  circular  orbits,  recommended  by  its 
simplicity  and  aesthetic  quality,  was  forced  to  give 
way  to  the  hypothesis  of  elliptical  orbits.  Newton's 
hypothesis  that  light  is  due  to  particles  emitted  by 
all  luminous  bodies  yielded,  at  least  for  the  time,  to 
the  theory  of  light  vibrations  in  an  ether  pervading 
all  space.  The  path  of  scientific  progress  is  strewn , 
with  the  ruins  of  overthrown  hypotheses.  Many  of 
the  defeated  assumptions  have  been  merely  implicit 
errors  of  the  man  in  the  street,  and  they  are  over- 
thrown not  by  facts  alone,  but  by  new  hypotheses 
verified  by  facts  and  leading  to  fresh  discoveries. 

According  to  John  Stuart  Mill,  "  It  appears  .  .  . 
to  be  a  condition  of  a  genuinely  scientific  hypothesis, 


SCIENTIFIC  HYPOTHESIS  257 

that  it  be  not  destined  always  to  remain  an  hypothe- 
sis, but  be  of  such  a  nature  as  to  be  either  proved 
or  disproved  by  that  comparison  with  observed  facts 
which  is  termed  Verification."  This  statement  is 
of  value  in  confirming  the  general  distrust  of  mere 
hypothesis,  and  in  distinguishing  between  the  unveri- 
fied and  unverifiable  presupposition  and  the  legiti- 
mate assumption  which  through  verification  may  be- 
come established  doctrine. 

REFERENCES 

J.  Cox,  Beyond  the  Atom,  1913  (Cambridge  Manuals  of  Science 

and  Literature). 

R.  K.  Duncan,  The  New  Knowledge,  1905. 
H.  PoincarS,  Science  and  Hypothesis. 

E.  Rutherford,  Radioactive  Substances  and  their  Radiations. 

F.  Soddy,  The  Interpretation  of  Radium. 

F.  Soddy,  Matter  and  Energy  (Home  University  Library). 
Sir  William  A.  Tilden,  Progress  of  Scientific  Chemistry  in  our  Own 
Time,  1913. 


CHAPTEE  XIX 

THE    SCIENTIFIC    IMAGINATION 

PSYCHOLOGY,  or  the  science  of  mental  life  as  re- 
vealed in  t behavior,  has  been  greatly  indebted  to 
physiologists  and  to  students  of  medicine  in  general. 
Any  attempt  to  catalogue  the  names  of  those  who 
have  approached  the  study  of  the  mind  from  the 
direction  of  the  natural  sciences  is  liable  to  prove 
unsatisfactory,  and  a  brief  list  is  sure  to  entail  many 
important  omissions.  The  mention  of  Locke,  Chesel- 
den,  Hartley,  Cabanis,  Young,  Weber,  Gall,  Miil- 
ler,  Du  Bois-Reymond,  Bell,  Magendie,  Helmholtz, 
Darwin,  Lotze,  Ferrier,  Goltz,  Munk,  Mosso,  Mauds- 
ley,  Carpenter,  Galton,  Hering,  Clouston,  James, 
Janet,  Kraepelin,  Flechsig,  and  Wundt  will,  however, 
serve  to  remind  us  of  the  richness  of  the  contribu- 
tion of  the  natural  sciences  to  the  so-called  mental 
science.  Indeed,  physiology  would  be  incomplete 
unless  it  took  account  of  the  functions  of  the  sense 
organs,  of  the  sensory  and  motor  nerves,  of  the  brain 
with  its  association  areas,  as  well  as  the  expression 
of  the  emotions,  and  the  changes  of  function  accom- 
panying the  development  of  the  nervous  system, 
from  the  formation  of  the  embryo  till  physical  disso- 
lution, and  from'  species  of  the  simplest  to  those  of 
the  most  complex  organization. 

At  the  beginning  of  the  nineteenth  century  the 
French  physician  Cabanis  was  disposed  to  identify 
human  personality  with  mere  nervous  organization 


THE  SCIENTIFIC  IMAGINATION     259 

reacting  to  physical  impressions,  and  to  look  upon 
the  brain  as  the  organ  for  the  production  of  mind. 
He  soon,  however,  withdrew  from  this  extreme  posi- 
tion and  expressed  his  conviction  of  the  existence  of 
an  immortal  spirit  apart  from  the  body.  One  might 
say  that  the  brain  is  the  instrument  through  which 
the  mind  manifests  itself  rather  than  the  organ  by 
which  mind  is  excreted.  Even  so,  it  must  be  agreed 
that  the  relation  between  the  psychic  agent  and  the 
physical  instrument  is  so  close  that  physiology  must 
take  heed  of  mental  phenomena  and  that  psychology 
must  not  ignore  the  physical  concomitants  of  mental 
processes.  Hence  arises  a  new  branch  of  natural 
science,  physiological  psychology,  or,  as  Fechner 
(1860),  the  disciple  of  Weber,  called  it,  psycho- 
physics. 

Through  this  alliance  between  the  study  of  the 
mind  and  the  study  of  bodily  functions  the  intelli- 
gence of  the  lower  animals  and  its  survival  value,  the 
mental  growth  of  the  child,  mental  deterioration  in 
age  and  disease,  and  the  psychological  endowments 
of  special  classes  or  of  individuals,  became  subjects 
for  investigation.  Now  human  psychology  is  recog- 
nized as  contributing  to  various  branches  of  anthro- 
pology, or  the  general  study  of  man. 

\Vilhelm  Wundt,  who,  as  already  implied,  had  ap- 
proached the  study  of  the  mind  from  the  side  of  the 
natural  sciences,  established  in  1875  at  the  University 
of  Leipzig  the  first  psycho-physical  institute  for  the 
experimental  study  of  mental  phenomena.  His  express 
purpose  was  to  analyze  the  content  of  consciousness 
into  its  elements,  to  examine  these  elements  in  their 
qualitative  and  quantitative  differences,  and  to  deter- 


260         THE  HISTORY  OF  SCIENCE 

mine  with  precision  the  conditions  of  their  existence 
and  succession.  Thus  science  after  contemplating  a 
wide  range  of  outer  phenomena  —  plants,  animals, 
earth's  crust,  heavenly  bodies,  molecules  and  atoms 
—  turns  its  attention  with  keen  scrutiny  inward  on 
the  thinking  mind,  the  subjective  process  by  which 
man  becomes  cognizant  of  all  objective  things. 

The  need  of  expert  study  of  the  human  mind  as 
the  instrument  of  scientific  discovery  might  have  been 
inferred  from  the  fact  that  the  physicist  Tyndall  read 
before  the  British  Association  in  1870  a  paper  on  the 
Scientific  Use  of  the  Imagination,  in  which  he  spoke 
of  the  imagination  as  the  architect  of  physical  theory, 
cited  Newton,  Dalton,  Davy,  and  Faraday  as  afford- 
ing examples  of  the  just  use  of  this  creative  power 
of  the  mind,  and  quoted  a  distinguished  chemist  as 
identifying  the  mental  process  of  scientific  discov- 
ery with  that  of  artistic  production.  Tyndall  even 
chased  the  psychologists  in  their  own  field  and  stated 
that  it  was  only  by  the  exercise  of  the  imagination  that 
we  could  ascribe  the  possession  of  mental  powers  to 
our  fellow  creatures.  "  You  believe  that  in  society 
you  are  surrounded  by  reasonable  beings  like  your- 
self. .  .  .  What  is  your  warrant  for  this  conviction  ? 
Simply  and  solely  this :  your  fellow-creatures  behave 
as  if  they  were  reasonable." 

On  the  traces  of  this  brilliant  incursion  of  the 
natural  philosopher  into  the  realm  of  mental  science, 
later  psychologists  must  follow  but  haltingly.  Just 
as  in  the  history  of  physics  a  long  series  of  studies 
intervened  between  Bacon's  hypothesis  that  heat  is 
a  kind  of  motion  (1620)  and  Tyndall's  own  work, 
Heat  as  a  Mode  of  Motion  (1863),  so  must  many 


THE  SCIENTIFIC  IMAGINATION     261 

psychological  investigations  be  made  before  an  ade- 
quate psychology  of  scientific  discovery  can  be  formu- 
lated. It  may  ultimately  prove  that  the  passages  in 
which  Tyndall  and  other  scientists  speak  of  scientific 
imagination  would  read  as  well  if  for  this  term,  in- 
tuition, inspiration,  unconscious  cerebration,  or  even 
reason  were  substituted. 

At  first  glance  it  would  seem  that  the  study  of  the 
sensory  elements  of  consciousness,  motor,  tactile, 
visual,  auditory,  olfactory,  gustatory,  thermal,  inter- 
nal, pursued  for  the  last  half  century  by  the  experi- 
mental method,  would  furnish  a  clue  to  the  nature  of 
the  imagination.  A  visual  image,  or  mental  picture, 
is  popularly  taken  as  characteristic  of  the  imaginative 
process.  In  fact,  the  distinguished  psychologist  Wil- 
liam James  devotes  the  whole  of  his  interesting 
chapter  on  the  imagination  to  the  discussion  of  dif- 
ferent types  of  imagery.  The  sensory  elements  of 
consciousness  are  involved,  however,  in  perception, 
memory,  volition,  reason,  and  sentiment,  as  they  are 
in  imagination.  They  have  been  recognized  as  fun- 
damental from  antiquity.  Nothing  is  in  the  intellect 
which  was  not  previously  in  the  senses.  To  be  out  of 
one's  senses  is  to  lack  the  purposive  guidance  of 
the  intelligence. 

The  psychology  of  individuals  and  groups  shows 
startling  differences  in  the  kind  and  vividness  of 
imagery.  Many  cases  are  on  record  where  the  mental 
life  is  almost  exclusively  in  visual,  in  auditory,  or  in 
motor  terms.  One  student  learns  a  foreign  language 
by  writing  out  every  word  and  sentence ;  another  is 
wholly  dependent  on  hearing  them  spoken  ;  a  third 
can  recall  the  printed  page  with  an  almost  photo- 


262         THE  HISTORY  OF  SCIENCE 

graphic  vividness.  The  history  of  literature  and  art 
furnishes  us  with  illustrations  of  remarkable  powers 
of  visualization.  Blake  and  Fromentin  were  able  to 
reproduce  in  pictures  scenes  long  retained  in  memory. 
The  latter  recognized  that  his  painting  was  not  an 
exact  reproduction  of  what  he  had  seen,  but  that  it 
was  none  the  less  artistic  because  of  the  selective  influ- 
ence that  his  mind  had  exerted  on  the  memory  image. 
Wordsworth  at  times  postponed  the  description  of  a 
scene  that  appealed  to  his  poetic  fancy  with  the  ex- 
press purpose  of  blurring  the  outlines,  but  enhancing 
the  personal  factor.  Goethe  had  the  power  to  call  up 
at  will  the  form  of  a  flower,  to  make  it  change  from 
one  color  to  another  and  to  unfold  before  his  mind's 
eye.  Professor  Dilthey  has  collected  many  other 
records  of  the  hallucinatory  clearness  of  the  visual 
imagery  of  literary  artists. 

On  the  other  hand,  Galton,  after  his  classical 
study  of  mental  imagery  (1883),  stated  that  scientific 
men,  as  a  class,  have  feeble  powers  of  visual  repre- 
sentation. He  had  appealed  for  evidence  of  visual 
recall  to  distinguished  scientists  because  he  thought 
them  more  capable  than  others  of  accurately  stating 
the  results  of  their  introspection.  He  had  recourse 
not  only  to  English  but  to  foreign  scientists,  includ- 
ing members  of  the  French  Institute.  "  To  my  aston- 
ishment," he  writes,  "  I  found  that  the  great  majority 
of  men  of  science  to  whom  I  first  applied  protested 
that  mental  imagery  was  unknown  to  them,  and  they 
looked  on  me  as  fanciful  and  fantastic  in  supposing 
that  the  words  4  mental  imagery '  really  expressed 
what  I  believed  everybody  supposed  them  to  mean. 
They  had  no  more  notion  of  its  true  nature  than  a 


THE   SCIENTIFIC   IMAGINATION     263 

color-blind  man,  who  has  not  discerned  his  defect, 
has  of  the  nature  of  color."  One  scientist  confessed 
that  it  was  only  by  a  figure  of  speech  that  he  could 
describe  his  recollection  of  a  scene  as  a  mental  image 
to  be  perceived  with  the  mind's  eye. 

When  Galton  questioned  persons  whom  he  met  in 
general  society  he  found  "an  entirely  different  dispo- 
sition to  prevail.  Many  men  and  a  yet  larger  number 
of  women,  and  many  boys  and  girls,  declared  that 
they  habitually  saw  mental  imagery,  and  that  it  was 
perfectly  distinct  to  them  and  full  of  color."  The 
evidence  of  this  difference  between  the  psychology 
of  the  average  distinguished  scientist  and  the  average 
member  of  general  society  was  greatly  strengthened 
upon  cross-examination.  Galton  attributed  the  differ- 
ence to  the  scientist's  "  habits  of  highly  generalized 
and  abstract  thought,  especially  when  the  steps  of 
reasoning  are  carried  on  by  words  [employed]  as 
symbols." 

It  is  only  by  the  use  of  words  as  symbols  that  sci- 
entific thought  is  possible.  It  is  through  cooperation 
in  work  that  mankind  has  imposed  its  will  upon  the 
creation,  and  cooperation  could  not  have  been  carried 
far  without  the  development  of  language  as  a  means  of 
communication.  Were  it  not  for  the  help  of  words 
we  should  be  dependent,  like  the  lower  animals,  on 
the  fleeting  images  of  things.  We  should  be  bound 
to  the  world  of  sense  and  not  have  range  in  the  world 
of  ideas.  Words  are  a  free  medium  for  thought,  for 
the  very  reason  that  they  are  capable  of  shifting 
their  meaning  and  taking  on  greater  extension  or  in- 
tension. For  example,  we  may  say  that  the  apple  falls 
because  it  is  heavy,  or  we  may  substitute  synonymous 


264         THE  HISTORY  OF  SCIENCE 

phraseology  that  helps  us  to  view  the  falling  apple  in 
its  universal  aspects.  The  mind  acquires  through 
language  a  field  of  activity  independent  of  the  ob- 
jective world.  We  have  seen  in  an  earlier  chapter 
that  geometry  developed  as  a  science  is  becoming 
gradually  weaned  from  the  art  of  surveying.  Tri- 
angles and  rectangles  cease  to  suggest  meadows,  or 
vineyards,  or  any  definite  imagery  of  that  sort,  and 
are  discussed  in  their  abstract  relationship.  Science 
demands  the  conceptual  rather  than  the  merely  sen- 
sory. The  invisible  real  world  of  atoms  and  cor- 
puscles has  its  beginning  in  the  reason,  the  word.  To 
formulate  new  truths  in  the  world  of  ideas  is  the  pre- 
rogative of  minds  gifted  with  exceptional  reason. 

To  be  sure,  language  itself  may  be  regarded  as  im- 
agery. Some  persons  visualize  every  word  spoken  as 
though  it  were  seen  on  the  printed  page  ;  others  can- 
not recall  a  literary  passage  without  motor  imagery 
of  the  speech  organs  or  even  incipient  speech ;  while 
others  again  experience  motor  imagery  of  the  writing 
hand.  With  many,  in  all  forms  of  word-conscious- 
ness, the  auditory  image  is  predominant.  In  the 
sense  of  being  accompanied  by  imagery  all  think- 
ing is  imaginative.  But  it  is  the  use  of  words 
that  permits  us  to  escape  most  completely  from  the 
more  primitive  forms  of  intelligence.  So  directly 
does  the  printed  word  convey  its  meaning  to  the 
trained  mind  that  to  regard  it  as  so  much  black  on 
white  rather  than  as  a  symbol  is  a  rare  and  rather 
upsetting  mental  experience.  Words  differ  among 
themselves  in  their  power  to  suggest  images  of  the 
thing  symbolized.  The  word  "  existence  "  is  less  image- 
producing  than  "  flower,"  and  "  flower  "  than  "  red 


THE   SCIENTIFIC   IMAGINATION     265 

rose."  It  is  characteristic  of  the  language  of  science 
to  substitute  the  abstract  or  general  expression  for 
the  concrete  and  picturesque. 

When,  therefore,  we  are  told  that  the  imagination 
has  been  at  the  bottom  of  all  great  scientific  discov- 
eries, that  the  discovery  of  law  is  the  peculiar  function 
of  the  creative  imagination,  and  that  all  great  scien- 
tists have,  in  a  certain  sense,  been  great  artists, 'we 
are  confronted  with  a  paradox.  In  what  department 
of  thought  is  imagination  more  strictly  subordinated 
than  in  science  ?  Genetic  psychology  attempts  to  trace 
the  development  of  mind  as  a  means  of  adjustment. 
It  examines  the  instincts  that  serve  so  wonderfully 
the  survival  of  various  species  of  insects.  It  studies 
the  more  easily  modified  instinct  of  birds,  and  notes 
their  ability  to  make  intelligent  choice  on  the  basis 
of  experience.  Does  the  bird's  ability  to  recognize 
imply  the  possession  of  memory,  or  imagery?  In- 
creased intelligence  assures  perpetuation  of  other 
species  in  novel  and  unforeseen  conditions.  The  more 
tenacious  the  memory,  the  richer  the  supply  of  images, 
the  greater  the  powers  of  adaptation  and  survival. 
We  know  something  concerning  the  motor  memory 
of  rodents  and  horses,  and  its  biological  value.  The 
child  inherits  less  definitely  organized  instincts,  but 
greater  plasticity,  than  the  lower  animals.  Its  mental 
life  ifc  a  chaos  of  images.  It  is  the  work  of  education 
to  discipline  as  well  as  to  nourish  the  senses,  to  teach 
form  as  well  as  color,  to  impart  the  clarifying  sense 
of  number,  weight,  and  measurement,  to  help  distin- 
guish between  the  dream  and  the  reality,  to  teach 
language,  the  treasure-house  of  our  traditional  wis- 
dom, and  logic,  so  closely  related  to  the  right  use  of 


266         THE  HISTORY  OF  SCIENCE 

language.  The  facts  of  abnormal,  as  well  as  those  of 
animal  and  child  psychology,  prove  that  the  subor- 
dination of  the  imagination  and  fancy  to  reason  and 
understanding  is  an  essential  factor  in  intellectual 
development. 

No  one,  of  course,  will  claim  that  the  mental  ac- 
tivity of  the  scientific  discoverer  is  wholly  unlike 
that  of  any  other  class  of  man ;  but  it  leads  only  to 
confusion  to  seek  to  identify  processes  so  unlike  as 
scientific  generalization  and  artistic  production.  The 
artist's  purpose  is  the  conveyance  of  a  mood.  The 
author  of  Macbeth  employs  every  device  to  impart  to 
the  auditor  the  sense  of  blood-guiltiness  ;  every  lurid 
scene,  every  somber  phrase,  serves  to  enhance  the 
sentiment.  A  certain  picture  by  Diirer,  a  certain 
poem  of  Browning's,  convey  in  every  detail  the  feel- 
ing of  dauntless  resolution.  Again,  a  landscape 
painter,  recognizing  that  his  satisfaction  in  a  certain 
scene  depends  upon  a  stretch  of  blue  water  with  a 
yellow  strand  and  old-gold  foliage,  proceeds  to  re- 
arrange nature  for  the  benefit  of  the  mood  he  desires 
to  enliven  and  perpetuate.  It  is  surely  a  far  cry  from 
the  attitude  of  these  artists  manipulating  impressions 
in  order  to  impart  to  others  an  individual  mood,  to 
that  of  the  scientific  discoverer  formulating  a  law 
valid  for  all  intellects. 

In  the  psychology  of  the  present  day  there  is  much 
that  is  reminiscent  of  the  biological  psychology  of 
Aristotle.  From  the  primitive  or  nutrient  soul  which 
has  to  do  with  the  vital  functions  of  growth  and  re- 
production, is  developed  the  sentient  soul,  concerned 
with  movement  and  sensibility.  Finally  emerges  the 
intellectual  and  reasoning  soul.  These  three  parts 


THE  SCIENTIFIC   IMAGINATION     267 

are  not  mutually  exclusive,  but  the  lower  foreshadow 
the  higher  and  are  subsumed  in  it.  Aristotle,  how- 
ever, interpreted  the  lower  by  the  higher  and  not 
vice  versa.  It  is  no  compliment  to  the  scientific  dis- 
coverer to  say  that  his  loftiest  intellectual  achievement 
is  closely  akin  to  fiction,  or  is  the  result  of  a  mere 
brooding  on  facts,  or  is  accompanied  by  emotional 
excitement,  or  is  the  work  of  blind  instinct. 

It  will  be  found  that  scientific  discovery,  while 
predominantly  an  intellectual  process,  varies  with  the 
nature  of  the  phenomena  of  the  different  sciences 
and  the  individual  mental  differences  of  the  discover- 
ers. As  stated  at  the  outset  the  psychology  of  scientific 
discovery  must  be  the  subject  of  prolonged  investi- 
gation, but  some  data  are  already  available.  One  great 
mathematician,  Poincare,  attributes  his  discoveries 
to  intuition.  The  essential  idea  comes  with  a  sense 
of  illumination.  It  is  characterized  by  suddenness, 
conciseness,  and  immediate  certainty.  It  may  come 
unheralded,  as  he  is  crossing  the  street,  walking  on 
the  cliffs,  or  stepping  into  a  carriage.  There  may 
have  intervened  a  considerable  period  of  time  free 
from  conscious  effort  on  the  special  question  involved 
in  the  discovery.  Poincare  is  inclined  to  account  for 
these  sudden  solutions  of  theoretical  difficulties  on 
the  assumption  of  long  periods  of  previous  uncon- 
scious work. 

There  are  many  such  records  from  men  of  genius. 
At  the  moment  the  inventor  obtains  the  solution  of 
his  problem  his  mind  may  seem  to  be  least  engaged 
with  it.  The  long-sought-for  idea  comes  like  an  in- 
spiration, something  freely  imparted  rather  than 
voluntarily  acquired.  No  mental  process  is  more 


268         THE  HISTORY  OF  SCIENCE 

worthy  to  command  respect ;  but  it  may  not  lie  be- 
yond the  possibility  of  explanation^  Like  ethical 
insight,  or  spiritual  illumination,  the  scientific  idea 
comes  to  those  who  have  striven  for  it.  The  door  may 
open  after  we  have  ceased  to  knock,  or  the  response 
come  when  we  have  forgotten  that  we  sent  in  a  call ; 
but  the  discovery  comes  only  after  conscious  work. 
The  whole  history  of  science  shows  that  it  is  to  the 
worker  that  the  inspiration  conies,  and  that  new 
ideas  develop  from  old  ideas. 

It  may  detract  still  further  from  the  mysterious- 
ness  of  the  discovery-process  to  add  that  the  illu- 
minating idea  may  come  in  the  midst  of  conscious 
work,  and  that  then  also  it  may  appear  as  a  sudden 
gift  rather  than  the  legitimate  outcome  of  mental 
effort.  The  spontaneity  of  wit  may  afford  another  clue 
to  the  mystery  of  scientific  discovery.  The  utterer  of 
a  witticism  is  frequently  as  much  surprised  by  it  as 
the  auditors,  probably  because  the  idea  comes  as 
verbal  imagery,  and  the  full  realization  of  their  sig- 
nificance is  grasped  only  with  the  actual  utterance  of 
the  words.  The  fact  that  to  the  scientific  discoverer 
the  solution  of  his  problem  arrives  at  the  moment 
when  it  is  least  sought  is  analogous  to  the  common 
experience  that  the  effort  to  recall  a  name  may  in- 
hibit the  natural  association. 

The  tendency  to  emphasize  unduly  the  role  played 
by  the  scientific  imagination  springs  probably  from  the 
misconception  that  the  imagination  is  a  psychological 
superfluity,  one  of  the  luxuries  of  the  mental  life, 
which  should  not  be  withheld  from  those  who  deserve 
the  best.  The  view  lingers  with  regard  to  the  aesthetic 
imagination.  James  could  not  understand  the  biologi- 


THE   SCIENTIFIC   IMAGINATION     269 

cal  function  of  the  aesthetic  faculty.  On  the  alleged 
uselessness  of  this  phase  of  the  human  mind  A.  J.  Bal- 
four  has  recently  based  an  argument  for  the  immortal- 
ity of  the  soul.  This  view  is  strikingly  at  variance 
with  that  which  inclines  to  identify  it  with  that  mental 
process  which  creates  scientific  theories  and  thus  paves 
the  way  for  the  adjustment  of  posterity  to  earthly 
conditions. 

REFERENCES 

Baldwin,  J.  M.,  History  of  Psychology,  1913.  2  vols. 

Dessoir,  Max,  Outlines  of  the  History  of  Psychology,  1912. 

Klemm,  Otto,  A  History  of  Psychology,  1914. 

Merz,  J.  T.,  History  of  European  Thought  in  the  Nineteenth  Cen- 
tury, vol.  ii,  chap,  xii,  On  the  Psycho-physical  View  of 
Nature. 

Rand,  Benjamin,  The  Classical  Psychologists,  1912. 

Ribot,  T.  A.,  English  Psychology,  1889. 

Ribot,  T.  A.,  German  Psychology  of  To-day,  1886. 


CHAPTER  XX 

SCIENCE    AND    DEMOCRATIC    CULTURE 

EDUCATION  is  the  oversight  and  guidance  of  the 
development  of  the  immature  with  certain  ethical 
and  social  ends  in  view.  Pedagogy,  therefore,  is  based 
partly  on  psychology  —  which,  as  we  have  seen  in 
the  preceding  chapter,  is  closely  related  to  the  bio- 
logical sciences  —  and  partly  on  ethics,  or  the  study 
of  morals,  closely  related  to  the  social  sciences.  These 
two  aspects  of  education,  the  psychological  and  the 
sociological,  were  treated  respectively  in  Rousseau's 
Emile  and  Plato's  Republic.  The  former  ill-under- 
stood work,  definitely  referring  its  readers  to  the 
latter  for  the  social  aspect  of  education,  applies  itself 
as  exclusively  as  possible  to  the  study  of  the  physical 
and  mental  development  of  the  individual  child. 
Rousseau  consciously  set  aside  the  problem  of  na- 
tionality or  citizenship;  he.  was  cosmopolitan,  and 
explicitly  renounced  the  idea  of  planning  the  educa- 
tion of  a  Frenchman  or  a  Swiss.  Neither  did  he  desire 
to  set  forth  the  education  of  a  wild  man,  free  and 
unrestrained.  He  wished  rather  to  depict  the  devel- 
opment of  a  natural  man  in  a  state  of  society ;  but 
he  emphasized  the  native  hereditary  endowment, 
while  expressing  his  admiration  for  Plato's  Republic 
as  the  great  classic  of  social  pedagogy.  The  titles  of  the 
two  works,  one  from  the  name  of  an  individual  child, 
the  other  from  a  form  of  government,  should  serve 
to  remind  us  of  the  purpose  and  limitations  of  each. 


DEMOCRATIC   CULTURE  271 

Plato's  thought  was  centered  on  the  educational 
and  moral  needs  of  the  city-state  of  Athens.  He  was 
apprehensive  that  the  city  was  becoming  corrupted 
through  the  wantonness  and  lack  of  principle  of  the 
Athenian  youth.  He  strove  to  rebuild  on  reasoned 
foundations  the  sense  of  social  obligation  and  re- 
sponsibility which  had  in  the  earlier  days  of  Athens 
rested  upon  faith  in  the  existence  of  the  gods.  As  a 
conservative  he  hoped  to  restore  the  ancient  Athenian 
feeling  for  duty  and  moral  worth,  and  he  even  en- 
vied some  of  the  educational  practices  of  the  rival 
city-state  Sparta,  by  which  the  citizen  was  subordi- 
nated to  the  state.  The  novel  feature  of  Plato's  ped- 
agogy was  the  plan  to  educate  the  directing  classes, 
men  disciplined  in  his  own  philosophical  and  ethical 
conceptions.  He  was,  in  fact,  an  intellectual  aristo- 
crat, and  spoke  of  democracy  in  very  ironical  terms, 
as  the  following  sentences  will  show :  — 

"  And  thus  democracy  comes  into  being  after  the 
poor  have  conquered  their  opponents.  .  .  .  And  now 
what  is  their  manner  of  life,  and  what  sort  of  a  gov- 
ernment have  they?  For  as  the  government  is,  such 
will  be  the  man.  ...  In  the  first  place,  are  they 
not  free  ?  and  the  city  is  full  of  freedom  and  frank- 
ness—  a  man  may  do  as  he  likes.  .  .  .  And  where 
freedom  is,  the  individual  is  clearly  able  to  order  his 
own  life  as  he  pleases  ?  .  .  .  Then  in  this  kind  of 
State  there  will  be  the  greatest  variety  of  human  na- 
tures ?  .  .  .  This  then  will  be  the  fairest  of  States, 
and  will  appear  the  fairest,  being  spangled  with  the 
manners  and  characters  of  mankind,  like  an  em- 
broidered robe  which  is  spangled  with  every  sort 
of  flower.  And  just  as  women  and  children  think 


272         THE  HISTORY  OF  SCIENCE 

variety  charming,  so  there  are  many  men  who  will 
deem  this  to  be  the  fairest  of  States.  .  .  .  And  is  not 
the  equanimity  of  the  condemned  often  charming  ? 
Under  such  a  government  there  are  men  who,  when 
they  have  been  sentenced  to  death  or  exile,  stay 
where  they  are  and  walk  about  the  world ;  the  gen- 
tleman [convict]  parades  like  a  hero,  as  though  no- 
body saw  or  cared.  .  .  .  See  too  .  .  .  the  forgiv- 
ing spirit  of  democracy  and  the  '  don't  care '  about 
trifles,  and  the  disregard  of  all  the  fine  principles 
which  we  solemnly  affirmed  .  .  .  how  grandly  does 
she  trample  our  words  under  her  feet,  never  giving 
a  thought  to  the  pursuits  which  make  a  statesman, 
and  promoting  to  honor  anyone  who  professes  to  be 
the  people's  friend.  .  .  .  These  and  other  kindred 
characteristics  are  proper  to  democracy,  which  is  a 
charming  form  of  government,  full  of  variety  and 
disorder,  and  dispensing  equality  to  equals  and  un- 
equals  alike.  .  .  .  Consider  now  .  .  .  what  manner 
of  man  the  individual  is  ...  he  lives  through  the 
day  indulging  the  appetite  of  the  hour ;  and  some- 
times he  is  lapped  in  drink  and  strains  of  the  flute; 
then  he  is  for  total  abstinence,  and  tries  to  get  thin ; 
then,  again,  he  is  at  gymnastics ;  sometimes  idling 
and  neglecting  everything,  then  once  more  living 
the  life  of  a  philosopher ;  often  he  is  in  politics,  and 
starts  to  his  feet  and  says  and  does  whatever  comes 
into  his  head ;  and,  if  he  is  emulous  of  anyone  who 
is  a  warrior,  off  he  is  in  that  direction,  or  of  men  of 
business,  once  more  in  that.  His  life  has  neither 
order  nor  law;  so  he  goes  on  continually,  and  he 
terms  this  joy  and  freedom  and  happiness.  Yes,  his 
life  is  all  liberty  and  equality.  Yes,  .  .  .  and  multi- 


DEMOCRATIC   CULTURE  273 

form,  and  full  of  the  most  various  characters ;  .  .  . 
he  answers  to  the  State,  which  we  described  as  fair 
and  spangled.  .  .  .  Let  him  then  be  set  over  against 
democracy ;  he  may  truly  be  called  the  democratic 
man." 

In  spite  of  the  satirical  tone  of  this  passage  much 
of  it  may  be  accepted  as  the  unwilling  tribute  of 
a  hostile  critic.  Democracy  is  the  triumph  of  the 
masses  over  the  oligarchs.  It  is  merciful  in  the  ad- 
ministration of  justice.  It  shows  a  magnanimous 
spirit  and  does  not  magnify  the  importance  of  trifles. 
It  prefers  the  rule  of  its  friends  to  the  rule  of  a 
despot.  Under  its  government  people  feel  themselves 
blessed  by  happiness,  liberty,  and  equality.  The 
culture  of  the  democratic  man  is  above  all  charac- 
terized by  adaptability. 

In  the  nineteenth  century  Matthew  Arnold,  the 
apostle  of  culture,  discussing  the  civilization  of  a 
democratic  nation  of  many  millions,  unconsciously 
confirmed  the  views  of  Plato  in  some  respects,  while 
showing  interesting  points  of  difference.  He  ex- 
pressed his  admiration  of  the  institutions,  solid  social 
conditions,  freedom  and  equality,  power,  energy,  and 
wealth  of  the  people  of  the  United  States.  In  the 
daintiness  of  American  house-architecture,  and  in 
the  natural  manners  of  the  free  and  happy  Amer- 
ican women  he  saw  a  real  note  of  civilization.  He 
felt  that  his  own  country  had  a  good  deal  to  learn 
from  America,  though  he  did  not  close  his  eyes  to 
the  real  dangers  to  which  all  democratic  nations  are 
exposed.  Arnold  failed  in  his  analysis  of  American 
civilization  to  confirm  Plato's  judgment  concerning 
the  variety  of  natures  to  be  found  in  the  democratic 


274         THE  HISTORY  OF  SCIENCE 

State,  as  well  as  tlie  Greek  philosopher's  censure 
that  democracy  shows  disregard  of  ethical  principles. 
In  fact,  Arnold  considered  the  people  of  the  United 
States  singularly  homogeneous,  singularly  free  from 
the  distinctions  of  class ;  "  we  [the  English]  are  so 
little  homogeneous,  we  are  living  with  a  system  of 
classes  so  intense,  that  the  whole  action  of  our  minds 
is  hampered  and  f  alsened  by  it ;  we  are  in  conse- 
quence wanting  in  lucidity,  we  do  not  see  clear  or 
think  straight,  and  the  Americans  have  here  much 
the  advantage  of  us."  As  for  the  second  point  of 
difference  between  Arnold  and  Plato,  the  English 
critic  recognized  that  the  American  people  belonged 
to  the  great  class  in  society  in  which  the  sense  of 
conduct  and  regard  for  ethical  principles  are  par- 
ticularly developed. 

Nearly  all  the  old  charges  against  American  democ- 
racy can  be  summarized  in  one  general  censure,  — 
the  lack  of  calm  and  reasoned  self-criticism,  —  and 
this  general  defect  is  rapidly  being  made  good.  It  is 
partly  owing  to  charity  and  good-will,  and  it  includes 
the  toleration  of  the  mediocre  or  inferior,  as,  for  ex- 
ample, in  the  theater ;  the  failure  to  recognize  dis- 
tinction, and  to  pay  deference  to  things  deserving  it ; 
the  glorification  of  the  average  man,  and  the  hustler, 
and  the  lack  of  special  educational  opportunities  for 
the  exceptionally  gifted  child.  That  criticism  as  an 
art  is  still  somewhat  behindhand  in  America  seems 
to  be  confirmed  by  comparing  French  and  American 
literary  criticism.  In  France  it  is  a  profession  prac- 
ticed by  a  corps  of  experts ;  in  America  only  a  very 
few  of  the  best  periodicals  can  be  relied  on  to  give 
reviews  based  on  critical  principles,  of  works  in  verse 


DEMOCRATIC   CULTURE  275 

or  prose.  (One  American  reviewer  confesses  that  in 
a  single  day  he  has  written  notices  of  twenty  new 
works  of  fiction,  his  work  bringing  him,  as  remu- 
neration, seventy-five  cents  a  volume.) 

There  is  no  evidence,  however,  that  Americans  as 
individuals  are  wanting  in  the  self-critical  spirit. 
And  for  Arnold  this  is  vital,  seeing  that  the  watch- 
word of  the  culture  he  proclaims  is  Know  Thyself. 
It  is  not  a  question  of  gaining  a  social  advantage  by 
a  smattering  of  foreign  languages.  It  is  more  than 
intellectual  curiosity.  "  Culture  is  more  properly  de- 
scribed as  having  its  origin  in  the  love  of  perfection. 
It  moves  by  the  force,  not  merely  or  primarily  of  the 
scientific  passion  for  pure  knowledge,  but  also  of 
the  passion  for  doing  good."  Human  perfection,  the 
essence  of  culture,  is  an  internal  condition,  but  the 
will  to  do  good  must  be  guided  by  the  knowledge  of 
what  is  good  to  do  ;  "  acting  and  instituting  are  of 
little  use  unless  we  know  how  and  what  we  ought  to 
act  and  institute."  Moreover,  "  because  men  are  all 
members  of  one  great  whole,  and  the  sympathy  which 
is  human  nature  will  not  allow  one  member  to  be 
indifferent  to  the  rest,  the  expansion  of  our  human- 
ity, to  suit  the  idea  of  perfection  which  culture  forms, 
must  be  a  general  expansion." 

For  Arnold's  contemporary  Nietzsche,  the  German 
exponent  of  Aristocracy,  the  expansion  of  education 
entailed  its  diminution.  For  him  ancient  Greece  was 
the  only  home  of  culture,  and  such  culture  was  not 
for  all  comers.  The  rights  of  genius  are  not  to  be 
democratized ;  not  the  education  of  the  masses,  but 
rather  the  education  of  a  few  picked  men  must  be 
the  aim.  The  one  purpose  which  education  should 


276        THE  HISTORY  OF  SCIENCE 

most  zealously  strive  to  achieve  is  the  suppression  of 
all  ridiculous  claims  to  independent  judgment,  and 
the  inculcation  upon  young  men  of  obedience  to  the 
scepter  of  genius.  The  scientific  man  and  the  cul- 
tured man  belong  to  two  different  spheres  which, 
though  coming  together  at  times  in  the  same  indi- 
vidual, are  never  fully  reconciled. 

In  order  to  appreciate  the  full  perverseness,  from 
the  democratic  standpoint,  of  Nietzsche's  view  of 
culture,  it  is  necessary  to  glance  at  his  political  ideals 
as  explained  by  one  of  his  sponsors.  Nietzsche  re- 
pudiates the  usual  conception  of  morality,  which  he 
calls  slave-morality,  in  favor  of  a  morality  of  mas- 
ters. The  former  according  to  him  encourages  the 
deterioration  of  humanity ;  the  latter  promotes  ad- 
vancement. He  favors  a  true  aristocracy  as  the  best 
means  of  producing  a  race  of  supermen.  "  Instead 
of  advocating  'equal  and  inalienable  rights  to  life, 
liberty,  and  the  pursuit  of  happiness,'  for  which 
there  is  at  present  such  an  outcry  (a  regime  which 
necessarily  elevates  fools  and  knaves,  and  lowers  the 
honest  and  intelligent),  Nietzsche  advocates  simple 
justice — to  individuals  and  families  according  to 
their  merits,  according  to  their  worth  to  society ; 
not  equal  rights,  therefore,  but  unequal  rights,  and 
inequality  in  advantages  generally,  approximately 
proportionate  to  deserts ;  consequently,  therefore,  a 
genuinely  superior  ruling  class  at  one  end  of  the 
social  scale,  and  an  actually  inferior  ruled  class,  with 
slaves  at  its  basis,  at  the  opposite  social  extreme." 

Since  it  is  the  view  of  this  aristocratic  philosopher 
that  science  is  the  ally  of  democracy  —  a  view  that 
every  chapter  of  the  history  of  science  serves  to  dem- 


DEMOCRATIC   CULTURE  277 

onstrate  —  it  is  of  interest  to  review  his  opinion  of 
the  character  of  the  scientist.  For  Nietzsche  the  sci- 
entist is  not  a  heroic  superman,  but  a  commonplace 
type  of  man,  with  commonplace  virtues.  He  lacks 
domination,  authority,  self-sufficiency;  he  is  rather 
in  need  of  recognition  from  others  and  is  character- 
ized by  the  self-distrust  innate  in  all  dependent  men 
and  gregarious  animals.  He  is  industrious,  patiently 
adaptable  to  rank  and  file,  equable  and  moderate  in 
capacity  and  requirement.  He  has  a  natural  feeling 
for  people  like  himself,  and  for  that  which  they  re- 
quire :  A  fair  competence  and  the  green  meadow 
without  which  there  is  no  rest  from  labor.  The 
scientist  shows  no  rapture  for  exalted  views ;  in 
fact,  with  an  instinct  for  mediocrity,  he  is  envious 
and  strives  for  the  destruction  of  the  exceptional 
man. 

A  training  in  natural  science  tends  to  make  one 
objective.  But  the  objective  man,  in  Nietzsche's 
opinion,  distrusts  his  own  personality  and  regards  it 
as  something  to  be  set  aside  as  accidental,  and  a 
detriment  to  calm  judgment.  The  temperamental 
philosopher  thinks  the  scientist  serene,  but  that  his 
serenity  springs  not  from  lack  of  trouble,  but  from 
incapacity  to  grasp  and  deal  with  his  own  private 
grief.  His  is  merely  disinterested  knowledge,  accord- 
ing to  Nietzsche.  The  scientist  is  emotionally  im- 
poverished. His  love  is  constrained,  and  his  hatred 
artificial ;  he  is  less  interesting  to  women  than  the 
warrior.  "  His  mirroring  and  externally  self-polished 
soul  no  longer  knows  how  to  affirm,  no  longer  how 
to  deny ;  he  does  not  command  ;  neither  does  he 
destroy."  As  we  see  in  the  case  of  Leibnitz,  the 


278         THE  HISTORY  OF  SCIENCE 

scientist  contemns  scarcely  anything  (Je  ne  meprise 
presque  rieri).  The  scientist  is  an  instrument,  but 
not  a  goal ;  he  is  something  of  a  slave,  nothing  in 
himself — presque  rien!  There  is  in  the  scientist 
nothing  bold,  powerful,  self-centered,  that  wants  to 
be  master.  He  is  for  the  most  part  a  man  without 
content  and  definite  outline,  a  selfless  man. 

This  educational  product,  which  the  builders  of 
modern  aristocracy  reject,  and  describe  after  their 
fashion,  we  accept  as  the  ally  of  the  masses  of  the 
people,  and  we  term  it  democratic  culture. 

The  objective  man,  at  the  same  time,  may  find 
even  in  the  vehement  pages  of  Nietzsche  warnings 
and  criticisms  which  the  friends  of  democracy  should 
not  disregard.  Extreme,  almost  insane,  as  his  doc- 
trine undoubtedly  is,  it  may  have  value  as  a  correc- 
tive influence,  an  antidote  for  other  extreme  views. 
It  serves  to  remind  us  that  democracy  may  be  mis- 
led by  feelings  in  themselves  noble,  and  may,  by 
grasping  what  seems  good,  miss  what  is  best.  For 
example,  there  are  in  the  United  States  about  three 
hundred  thousand  persons,  defective  or  subnormal 
mentally ;  there  is  a  smaller  number  of  persons  excep- 
tionally gifted  mentally.  It  is  a  poor  form  of  social 
service  that  would  exhaust  the  resources  of  science 
and  philanthropy  to  care  for  the  former  without 
making  any  special  provision  for  the  latter.  Genius 
is  too  great  an  asset  to  be  wasted  or  misapplied.  All 
culture  would  have  suffered  if  Newton  had  been 
held,  in  his  early  life,  to  exacting  administrative 
work ;  or  if  Darwin  had  devoted  his  years  to  allevi- 
ating the  conditions  of  the  miners  of  Peru  whose 
misery  touched  him  so  profoundly ;  or  if  Pasteur  had 


DEMOCRATIC   CULTURE  279 

been  taken  from  the  laboratory  and  pure  science  to 
make  a  country  doctor.  Nor  can  democracy  rest  sat- 
isfied with  any  substitute  for  culture  which  would 
disregard  what  is  great  in  literature,  in  art,  and  in 
philosophy,  or  which  would  ignore  history,  and  the 
languages  and  civilizations  of  the  past,  as  if  culture 
had  its  beginning  yesterday. 

In  this  chapter  we  have  considered  democracy  and 
democratic  culture  from  the  standpoint  of  three 
writers  on  education,  a  Greek  aristocrat,  a  German 
advocate  of  the  domination  of  the  classes  over  the 
masses,  and  an  Oxford  professor,  all  by  training  and 
temperament  more  or  less  hostile  critics.  A  more 
direct  procedure  might  have  been  employed  to  es- 
tablish the  claim  of  science  to  afford  a  basis  of  intel- 
lectual and  social  homogeneity.  A  brilliant  literary 
man  of  the  present  day  considers  that  places  in  the 
first  ranks  of  literature  are  reserved  for  the  doctri- 
nally  heterodox.  None  of  the  great  writers  of  Europe, 
he  asserts,  have  been  the  adherents  of  the  traditional 
faith.  (He  makes  an  exception  in  favor  of  Racine : 
but  this  is  a  needless  concession,  for  Racine  owed 
his  early  education  to  the  Port  Royalists,  became 
alienated  from  them  and  wrote  under  the  inspiration 
of  the  idea  of  the  moral  sufficiency  of  worldly  honor ; 
then,  after  an  experience  that  shook  his  faith  in  his 
own  code,  he  returned  to  the  early  religious  influ- 
ences in  his  life  and  composed  his  Esther  and  Atha~ 
lie.)  But,  unlike  literature,  the  study  of  science  is 
not  exclusive.  In  the  front  ranks  of  science  stand  the 
devout  Roman  Catholic  Pasteur,  the  Anglican  Dar- 
win, the  Unitarian  Priestley,  the  Calvinist  Faraday, 
the  Quakers  Dalton,  Young,  and  Lister,  Huxley  the 


280        THE  HISTORY  OF  SCIENCE 

Agnostic,  and  Aristotle  the  pagan  biologist.  Science 
has  no  Test  Acts. 

That  the  cultivation  of  the  sciences  tends  to  pro- 
mote a  type  of  culture  that  is  democratic  rather  than 
aristocratic,  sympathetic  rather  than  austere,  inclu- 
sive rather  than  exclusive,  is  further  witnessed  by 
the  fact  that  the  tradesman  and  artisan,  as  well  as 
the  dissenter,  play  a  large  part  in  their  development. 
We  have  seen  that  Pasteur  was  the  son  of  a  tan- 
ner, Priestley  of  a  cloth-maker,  Dalton  of  a  weaver, 
Lambert  of  a  tailor,  Kant  of  a  saddler,  Watt  of  a 
shipbuilder,  Smith  of  a  farmer.  John  Ray  was,  like 
Faraday,  the  son  of  a  blacksmith.  Joule  was  a 
brewer.  Davy,  Scheele,  Dumas,  Balard,  Liebig, 
Wohler,  and  a  number  of  other  distinguished  chem- 
ists, were  apothecaries'  apprentices.  Franklin  was 
a  printer.  At  the  same  time  other  ranks  of  society 
are  represented  in  the  history  of  science  by  Boyle, 
Cavendish,  Lavoisier.  The  physicians  and  the  sons 
of  physicians  have  borne  a  particularly  honorable 
part  in  the  advancement  of  physical  as  well  as  men- 
tal science.  The  instinctive  craving  for  power,  the 
will  to  dominate,  of  which  Nietzsche  was  the  lyricist, 
was  in  these  men  subdued  to  patience,  industry,  and 
philanthropy.  The  beneficent  effect  of  their  activities 
on  the  health  and  general  welfare  of  the  masses  of 
the  people  bears  witness  to  the  sanity  and  worth  of 
the  culture  that  prompted  these  activities. 

As  was  stated  at  the  outset  of  this  chapter,  educa- 
tion is  the  oversight  and  guidance  of  the  development 
of  the  immature  with  certain  ethical  and  social  ends 
in  view.  The  material  of  instruction,  the  method  of 
instruction,  and  the  type  of  educational  institution, 


DEMOCRATIC   CULTURE  281 

will  vary  with  the  hereditary  endowment,  age,  and 
probable  social  destiny  of  the  child.  In  a  democratic 
country  likely  to  become  more,  rather  than  less,  demo- 
cratic, those  subjects  will  naturally  be  taught  which 
have  vital  connection  with  the  people's  welfare  and 
progress  in  civilization.  At  the  same  time  the  method 
of  instruction  will  be  less  dogmatic  and  more  in- 
clined (under  a  free  than  under  an  absolute  govern- 
ment) to  evoke  the  child's  powers  of  individual  judg- 
ment ;  arbitrary  discipline  must  yield  gradually  to 
self-discipline.  The  changes  here  indicated  as  de- 
sirable are  already  well  under  way  in  America.  As 
regards  types  of  educational  institution,  it  is  signifi- 
cant that  America  about  the  middle  of  the  eighteenth 
century  introduced  the  Miltonic,  nonconformist 
Academy,  with  its  science  curriculum,  in  place  of 
the  traditional  Latin  grammar  school.  Later  the 
American  high  school,  institutions  of  which  type  now 
have  over  a  million  pupils,  and  teach  science  by  the 
heuristic  laboratory  method,  became  the  popular  form 
of  secondary  school.  It  is,  likewise,  not  without 
social  significance  that  the  Kindergarten  was  sup- 
pressed in  Prussia  after  the  revolt  of  the  people  in 
the  middle  of  the  nineteenth  century,  and  that  it 
found  a  more  congenial  home  in  a  democratic  coun- 
try. Its  educational  ideal  of  developing  self-activity 
without  losing  sight  of  the  need  of  social  adapta- 
tion finds  its  corollary  in  systematic  teaching  of  the 
sciences  in  relation  both  to  the  daily  work  and  to 
their  historical  and  cultural  antecedents. 


282         THE  HISTORY  OF  SCIENCE 


REFERENCES 

Matthew  Arnold,  Essays  in  Criticism,  and  Culture  and  Anarchy. 

Matthew  Arnold,  Civilization  in  the  United  States. 

Friedrich  Nietzsche,  On  the  Future  of  our  Educational  Institu- 
tions, vol.  vi,  of  the  Complete  Works;  translation  edited  by 
Dr.  Oscar  Levy. 

Friedrich  Nietzsche,  Beyond  Good  and  Evil,  vol.  v,  chap,  vi,  of 
the  Complete  Works. 

Plato,  Republic,  Book  viu;  vol.  in,  of  Benjamin  Jowett's  trans- 
lation of  the  Dialogues  of  Plato,  1875. 


INDEX 


Academic  des  Sciences,  111,  112. 

Academy,  at  Athens,  19;  Mil- 
ton's plan,  102;  Defoe's,  116; 
Franklin's,  125;  type  of  sec- 
ondary school,  282. 

Adams,  John  Couch,  188  et  seq. 

Aerodynamics,  233. 

Agricola,  George,  129. 

Agriculture,  12, 38, 107, 126, 137. 

Air,  157. 

Air  craft,  71,  126,  231  et  seq. 

Air-pump,  96. 

Akademie  der  Wissenschaften, 
113. 

Albertus  Magnus,  53. 

Alchemy,  50,  252. 

Alcuin,  52. 

Alexandria,  19,  44  et  seq. 

Algebra,  49. 

Alkaline  earths,  179. 

American  Philosophical  Society, 
121. 

Anatomy,  6,  8,  38,  50,  78. 

Anemometer,  107,  235. 

Anthrax,  224  et  seq. 

Antipodes,  37,  48. 

Antiseptic  surgery,  220,  231. 

Application,  30  et  seq. 

Aqua  rcgia,  51,  132. 

Aqueducts,  33. 

Aqueous  vapor,  157  et  seq. 

Arago,  184. 

Archimedes,  27. 

Architecture,  30  et  seq. 

Archytas,  18. 

Aristotle,  20  et  seq.,  49,  51,  53, 
266. 

Arithmetic,  6,  11,  48. 


Arnold,  Matthew,  273. 

Astrology,  10. 

Astronomy,  (Egyptian  and  Ba- 
bylonian) 2  et seq.;  (Greek)  16; 
(Roman)  34;  (Alexandrian)  45; 
(Hindu)  48;  (Arabian)  49,  50; 
(Copernican)  55  ;  (Tycho 
Brahe  and  Kepler)  87  et  seq.; 
(Newton)  110  et  seq.;  (nebu- 
lar hypothesis)  142  et  seq.; 
(discovery  of  Neptune)  184 


Atmosphere,  157. 

Atomic  Theory,  158  et  seq.,  250. 

Atoms,  17,  148,  158,  253. 

Augustus  Ceesar,  36. 

Averroes,  51  et  seq. 

Avicenna,  51. 

Avogadro,  165. 

Babylonia,  1  et  seq. 

Bacon,  Francis,  57  et  seq.,  80  et 

seq.,  105;  Baconian  principles, 

211. 

Bacon,  Roger,  54. 
Bacteria,  93. 
Bacteriology,  213  et  seq. 
Bagdad,  49. 
Barbarians,  46. 
Barometer,  94  et  seq. 
Basalt,  131,  132,  136,  137,  201. 
Becquerel,  233,  246  et  seq. 
Beddoes,  173. 
Beer,  223,  226. 
Berzelius,  162. 
Bessel,  187. 
Biology,  6,  7,  23  et  seq.,  37,  53, 

78,  109,  197  et  seq.,  213. 


284 


INDEX 


Biot,  215  et  seq. 

Black,  129,  133. 

Bodes  Law,  189. 

Botany,  6,  26,  37,  39,  53,  231 

et  seq. 

Bouvard,  Alexis,  185. 
Bouvard,  Eugene,  187. 
Boyle,  96,  107. 
Buffon,  130,  135. 
Building  material,  32. 

Cabanis,  258. 

Cairo,  49. 

Calendar,  9,  36. 

Carbonic  acid,   138,   155,   157, 

217. 

Carlisle,  177. 
Cato,  35,  38. 
Challis,  189. 
Charlemagne,  52. 
Charles  II,  105. 
Chemical  affinity,  159,  253. 
Chemistry,  6,  8,  50,  51,  155  et 

seq.,  170  et  seq.,  245  et  seq. 
Chicken  cholera,  225. 
Chlorine,  180. 
Clocks,  89,  94. 
Collinson,  123. 
Columbus,  26,  54. 
Columella,  38. 
Comenius,  100. 
Comets,  10,  40,  149. 
Conservation  of  energy,  168. 
Constantine,  37. 
Copernicus,  55. 
Coral  reefs,  203. 
Cordova,  50. 

Counting,  6,  11,  34,  49,  86. 
Cowley,  104  et  seq. 
Cronstedt,  130. 
Curie,  P.  and  S.,  247  et  seq. 

D'Alembert,  58. 
Dalton,  155,  157  et  seq. 


Darwin,  Charles,  ]  98  et  seq. 

Darwin,  Erasmus,  199. 

Davy,  122,  163,  170  et  seq. 

Deduction,  82. 

Defoe,  116. 

Democratic  culture,  44,  270  et 

seq. 

Democritus,  17,  48,  148. 
Descartes,  57,  72,  82  et  seq. 
Desmarest,  132. 
Dialogues  of  Plato,  19. 
Diderot,  58. 
Dioscorides,  39. 
Dyes,  24,  33,  71,  181. 

Earthquakes,  40,  137. 
Ebers  papyrus,  7. 
Eclipses,  10,  16,  49. 
Education,  19,  35,  36,  40,  44,  52, 

53,  100  et  seq.,  116,  122,  123, 

171-72,  198,  213,    214,   216, 

270  et  seq. 
Egypt,  1  et  seq. 
Electricity,  75,  123  et  seq.,  177, 

231. 

Electrolysis,  178. 
Elements,  17,  20,  22,  155. 
Ellipse,  20. 
Embalmers,  7. 
Empedocles,  17,  40. 
Encyclopaedia,  58. 
Ethics,  21,  40,  41. 
Euclid,  18,  19. 
Evelyn,  109. 
Experiment,  72  et  seq. 
Extinction,  206. 

Faraday,  181. 
Fermentation,  216  et  seq. 
Fitzroy,  198. 
Flacherie,  221. 
Flamsteed,  110,  111,  184. 
Fossils,  140. 
Franklin,  15,  114. 


INDEX 


285 


Galen,  38,  79. 
Galileo,  75  et  seq.,  95. 
Galipagos  Archipelago,   208  et 

seq. 

Galle,  193. 
Gallon,  258. 
Galvani,  177. 
Gascoigne,  93. 
Gassendi,  99. 
Gay-Lussac,  164,  181. 
Geber,  177. 
Geology,  129  et  seq. 
Geometry,  4, 15, 18,  19, 84,  264. 
Gerbert,  53. 
Gilbert,  72,  74,  76. 
Glen  Tilt,  136. 
Gnomon,  13,  33. 
Granite,  131. 
Graunt,  105,  109. 
Gravity,  110  et  seq. 
Greece,  15  et  seq. 
Gresham  College,  101,  106. 
Grew,  109. 
Guericke,  96. 

Hall,  Sir  James,  129,  137  et  seq. 

Halley,  110,  112,  186. 

Hammurabi,  12. 

Hartley,  172,  258. 

Hartlib,  99. 

Harun  Al-Rashid,  48. 

Heat,  82, 155, 156, 166, 168, 173. 

Heliacal  rising,  4. 

Helmholtz,  168,  258. 

Henry,  238. 

Heraclitus,  17. 

Herschel,  Sir  John,  192. 

Herschel,  Sir  William,  152  et 
seq.,  184. 

Hindu  arithmetic  and  astron- 
omy, 48,  49. 

Hipparchus,  27,  45. 

Hippocrates,  27. 

Hobbes,  99. 


Homology,  26. 

Hooke,  107,  109. 

Hope,  138. 

Horrocks,  109. 

Horse,  204. 

Horticulture,  40. 

Hugo  of  St.  Victor,  60. 

Humboldt,  131,  201. 

Hussey,  186. 

Hutton,  132  et  seq. 

Huygens,  94,  111. 

Hydrophobia,  207,  227  et  seq.    ' 

Hypatia,  46,  48. 

Hypothesis,  147,  150,  USetseq. 

I^-em-hetep,  6. 
Ilu-bani,  12. 
Induction,  81,  177. 
Industries,  8,  27,  68  et  seq.t  173, 

182,  220,  223,  226. 
Inoculation,  126. 
Inventions,  107,  233  et  seq. 
Invisible  College,  103. 
Iodine,  181. 
Iron,  8,  13,  182. 
Isidore  of  Seville,  60. 

James,  William,  258,  261,  268. 
Joule,  155,  167  et  seq. 
Julius  Caesar,  36. 

Kant,  142,  145  et  seq. 
Kepler,  90  et  seq.,  110.    ' 
Kindergarten,  281. 
Kircher,  93. 

Lactantius,  48. 
Lambert,  142,  149  et  seq. 
Langley,  231  et  seq. 
Laplace,  112,  150  et  seq. 
Laurium,  27. 
Lava,  138. 
Lavoisier,  156,  172. 
Leeuwenhoek,  93. 


286 


INDEX 


Leibnitz,  106,  112,  277. 
Lenses,  40,  50. 
Leonardo  da  Vinci,  72. 
Leverrier,  190  et  seq. 
Libraries,  46,  48,  121. 
Lincoln,  43  et  seq. 
Linnaeus,  130. 
Lippershey,  92. 
Lister,  213,  220,  223. 
Locke,  116,  172,  258. 
Logarithms,  91. 
Logic,  21,  53. 
Lucretius,  40. 
Lyell,  197,  201. 

Magnetism,  75,  127. 

Magnifiers,  40. 

Malpighi,  93,  106,  109. 

Malthus,  121,  211. 

Manchester,  157. 

Marble,  139. 

Mars,  10,  91. 

Marsh  gas,  126,  163,  182. 

Materia  medica,  39,  51. 

Mathematics,  4,  5,  6,  10,  11,  15, 

17,  18,  19,  34,  48,  49,  55,  87 

et  seq.,  110  et  seq.,  184  et  seq., 

264. 

Maupertuis,  145. 
Mayow,  156. 

Measuring,  5,  10,  86  et  seq. 
Mechanics,  18,  77,  231  et  seq. 
Medicine,  6, 11,  27,  34,  126,  173 

et  seq.,  207,  216  et  seq. 
Mensuration,  5,  92. 
Mental  imagery,  263. 
Mercury,  50,  51,  156. 
Mersenne,  99,  112. 
Metallurgy,  8,  13,  23,  50. 
Meteorology,  122,  133,  158. 
Microscope,  93. 
Milky  Way,  144. 
Mill,  John  Stuart,  256. 
Milton,  102,  213. 


Mineralogy,  130. 
Minute  and  second,  46. 
Monochord,  17. 
Monte  Cassino,  52. 
Moray,  104,  112. 
Murex,  24,  33. 

Napier,  91. 

Napoleon  I,  151,  177,  214. 

Napoleon  III,  221. 

Natural  history,  23,  37,  52,  61. 

Navigation,  3,  16,  26,  54,  126, 

231. 

Nebular  hypothesis,  147,  150. 
Neptune,  184  et  seq. 
Neptunist,  131. 
New  Atlantis,  71,  100,  183. 
Newton,  110,  135,  158. 
Nicholson,  177. 
Nietzsche,  277  et  seq. 
Nitric  oxide,  156,  161. 
Nitrous  oxide,  174. 
Novum  Organum,  70,  72. 
Numerals,   6,   11,   34,   49,   87, 

231. 

Observatories,  4,  49. 
Occupations,  12,51, 58, 68  etseq.t 

107. 

Optics,  50,  54,  93. 
Organic  remains,  126,  140. 
Origin  of  the  sciences,  1  et  seq. 
Origin  of  Species,  201. 

Pansophy,  100. 

Pascal,  95,  117. 

Pasteur,  213  et  seq. 

Pearson,  Karl,  60. 

Peirce,  195. 

Pepys,  110. 

Petty,  103,  122. 

Peurbach,  55. 

Philosophical  Transactions,  109. 

Philosophy,  15  et  seq.,  134. 


INDEX 


287 


Physics,  21,  28,  31,  32,  50,  54, 
74  et  seq.,  94  et  seq.,  110  el  seq., 
123,  155  et  seq.,  170  et  seq., 
231  et  seq.,  245  et  seq. 

Physiology,  6,  21,  38,  78,  173 
et  seq.,  225  et  seq. 

Picard,  111. 

Plato,  18,  270  et  seq. 

Play  fair,  133,  137. 

Pliny,  37. 

Pneumatic  Institution,  173. 

Poincare,  Henri,  255,  267. 

Port  Royal,  116,  279. 

Potash,  23,  51,  179. 

Potassium,  179. 

Precession  of  the  equinoxes,  10, 
112. 

Priestley,  126,  156. 

Primitive  man,  206. 

Principia,  110,  114. 

Prism,  40. 

Protyl,  254. 

Psychology,  23,  256  et  seq. 

Ptolemy,  45,  55. 

Pythagoras,  17. 

Quadrants,  50,  86. 
Quintilian,  39. 

Rabies,  227  et  seq. 

Racemic  acid,  215. 

Radioactivity,  245  et  seq. 

Ramsay,  246. 

Ray,  110. 

Regiomontanus,  55. 

Religion,  3,  8,  10,  40,  43  et  seq., 

142  et  seq. 
Rey,  94. 

Rhind  papyrus,  6. 
Rontgen  rays,  231. 
Rousseau,  270. 
Royal  Institution,  176. 
Royal   Society    of    Edinburgh, 

133. 


Royal  Society  of  London,  99  et 

seq. 

Rumford,  166. 
Rutherford,  247  et  seq. 

St.  Benedict,  52. 

St.  Thomas  Aquinas,  53. 

Saturn,  2,  92,  145. 

Saussure,  133. 

Scheele,  156,  180. 

Scientific  apparatus,  17,  49,  86 

et  seq. 

Scotus  Erigena,  53. 
Seneca,  40. 
Shaftesbury,  117. 
Signs  of  zodiac,  9,  33. 
Silkworm,  109,  221  et  seq. 
Siphon,  95. 
Sirius,  4. 

Smith,  Adam,  121,  133,  256. 
Smith,  William,  139  et  seq. 
Smithsonian    Institution,    193, 

233,  238. 
Socrates,  44,  117. 
Soda,  8,  51,  179. 
Soddy,  248  et  seq. 
Sodium,  179. 
Sosigenes,  36. 
Sound,  33. 

Species,  24,  197  et  seq. 
Specific  gravity,  28,  36,  50. 
Spectrum  analysis,  153,  231. 
Sphericity    of    the    earth,    26, 

37. 

Spontaneous  generation,  25, 218. 
Sprat,  105,  109. 
Steel,  8,  23. 
Sundial,  13. 
Survival,  206. 
Syntaxis,  45. 

Tables,  astronomical,  49,  50,  91, 

185  et  seq. 
Tanning,  177. 


288 


INDEX 


Technology,  5,  16,  20,  27,  30  et 
seq.,  50,  68  et  seq.,  86  et  seq., 
103,  107,  126,  129,  130,  139- 
41, 156, 160, 167, 177, 182, 231. 

Thales,  15. 

Theology,  47,  62,  172. 

Theon,  46. 

Theophrastus,  26,  39. 

Theory,  30,  41;  T.  of  the  Earth, 
133. 

Tides,  38,  112. 

Torricelli,  95. 

Trade  and  trades,  12,  51,  68 
et  seq.,  107,  115,  118. 

Transformation  Theory,  249 
et  seq. 

Trigonometry,  46,  49,  55. 

Turgot,  121. 

Tycho  Brahe,  87  et  seq. 

Tyndall,  260-61. 

Uranus,  184  et  seq. 

Vacuum,  95. 
Varro,  38. 
Vesalius,  78. 
Vitruvius,  30  et  seq. 
Viviani,  94. 
Vivisection,  38,  71,  80. 
Volcanoes,  40,  136. 
Volta,  177. 
Vulcanist,  131,  137. 


Wadham  College,  104. 
Walker,  195. 
Wallace,  211,  231. 
Wallis,  103. 

War,  46,  178,  213  et  seq. 
War-engines,  28,  34. 
Watch,  94. 
Water,  157,  177. 
Water-clocks,  13,  94. 
Watt,  Gregory,  172. 
Watt,  James,  133,  156,  157. 
Wedgwoods,  138,  173,  199. 
Weighing,  7,  10,  86. 
Werner,  129  et  seq. 
Wilkins,  101,  104. 
Willis,  104. 
Willughby,  109,  110. 
Wine,  220,  226. 
Wollaston,  119. 
Wool,  226. 
Wren,  104,  107. 
Wright,  143  et  seq. 
Wundt,  258,  259. 

Xenophon,  117. 
Young,  258,  279. 

Zacharias,  92. 
Zodiac,  9,  33. 

Zoology,  7,   12,  21,  24,  25,  37. 
53,  66,  109,  110,  197  et  seq.'i 


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